[go: nahoru, domu]

Files app: Stop auto-generating JS module for externs folder

* background_window.js
* command_handler_deps.js
* directory_change_event.js
* drive_dialog_controller.js
* entries_changed_event.js
* entry_location.js
* exif_entry.js
* files_app_entry_interfaces.js
* metadata_worker_window.js
* progress_center_panel.js
* volume_manager.js
* volume_info.js
* volume_info_list.js

Bug: 1214953
Change-Id: I06c310608c49cef951e2b20ca0c9d5cdb63f95aa
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2973255
Commit-Queue: Luciano Pacheco <lucmult@chromium.org>
Auto-Submit: Luciano Pacheco <lucmult@chromium.org>
Reviewed-by: Jeremie Boulic <jboulic@chromium.org>
Cr-Commit-Position: refs/heads/master@{#894639}
diff --git a/chrome/test/BUILD.gn b/chrome/test/BUILD.gn
index bc86c108..0fdd6e6 100644
--- a/chrome/test/BUILD.gn
+++ b/chrome/test/BUILD.gn
@@ -2150,7 +2150,6 @@
         "//testing/buildbot/filters:chromeos_filters",
         "//ui/file_manager:unit_test_data",
         "//ui/file_manager/file_manager/common/js:modulize_runtime_data",
-        "//ui/file_manager/file_manager/externs:modulize_runtime_data",
         "//ui/file_manager/file_manager/foreground/js:modulize_runtime_data",
       ]
 
diff --git a/ui/file_manager/BUILD.gn b/ui/file_manager/BUILD.gn
index 2dae24b..6705b8ff 100644
--- a/ui/file_manager/BUILD.gn
+++ b/ui/file_manager/BUILD.gn
@@ -85,7 +85,20 @@
     "audio_player/js/metadata_worker.js",
     "audio_player/js/test_util.js",
 
-    # Metadata:
+    # Externs:
+    "file_manager/externs/progress_center_panel.js",
+    "file_manager/externs/metadata_worker_window.js",
+    "file_manager/externs/files_app_entry_interfaces.js",
+    "file_manager/externs/exif_entry.js",
+    "file_manager/externs/entry_location.js",
+    "file_manager/externs/entries_changed_event.js",
+    "file_manager/externs/drive_dialog_controller.js",
+    "file_manager/externs/directory_change_event.js",
+    "file_manager/externs/command_handler_deps.js",
+    "file_manager/externs/background_window.js",
+    "file_manager/externs/volume_info_list.js",
+    "file_manager/externs/volume_info.js",
+    "file_manager/externs/volume_manager.js",
     "file_manager/externs/background/import_history.js",
     "file_manager/externs/background/task_queue.js",
     "file_manager/externs/background/progress_center.js",
@@ -97,6 +110,8 @@
     "file_manager/externs/background/crostini.js",
     "file_manager/externs/background/background_base.js",
     "file_manager/externs/background/file_browser_background_full.js",
+
+    # Metadata:
     "file_manager/foreground/js/metadata/content_metadata_provider.js",
     "file_manager/foreground/js/metadata/byte_reader.js",
     "file_manager/foreground/js/metadata/thumbnail_model.js",
@@ -292,21 +307,6 @@
     "file_manager/common/js/volume_manager_types.m.js",
     "file_manager/common/js/xfm.m.js",
 
-    # Externs:
-    "file_manager/externs/background_window.m.js",
-    "file_manager/externs/command_handler_deps.m.js",
-    "file_manager/externs/directory_change_event.m.js",
-    "file_manager/externs/drive_dialog_controller.m.js",
-    "file_manager/externs/entry_location.m.js",
-    "file_manager/externs/entries_changed_event.m.js",
-    "file_manager/externs/exif_entry.m.js",
-    "file_manager/externs/files_app_entry_interfaces.m.js",
-    "file_manager/externs/metadata_worker_window.m.js",
-    "file_manager/externs/progress_center_panel.m.js",
-    "file_manager/externs/volume_info.m.js",
-    "file_manager/externs/volume_info_list.m.js",
-    "file_manager/externs/volume_manager.m.js",
-
     # Files app Foreground:
     "file_manager/foreground/js/actions_controller.m.js",
     "file_manager/foreground/js/actions_model.m.js",
@@ -381,7 +381,6 @@
   deps = [
     "//ui/file_manager/audio_player/elements:web_components",
     "//ui/file_manager/file_manager/common/js:modulize",
-    "//ui/file_manager/file_manager/externs:modulize",
     "//ui/file_manager/file_manager/foreground/elements:elements",
     "//ui/file_manager/file_manager/foreground/elements:web_components",
     "//ui/file_manager/file_manager/foreground/js:modulize",
@@ -442,11 +441,6 @@
       "file_manager/common/js/test_error_reporting.m.js",
       "file_manager/common/js/volume_manager_types.m.js",
       "file_manager/common/js/xfm.m.js",
-      "file_manager/externs/entry_location.m.js",
-      "file_manager/externs/files_app_entry_interfaces.m.js",
-      "file_manager/externs/volume_info.m.js",
-      "file_manager/externs/volume_info_list.m.js",
-      "file_manager/externs/volume_manager.m.js",
 
       "file_manager/background/js/main_background.m.rollup.js",
       "file_manager/background/js/runtime_loaded_test_util.rollup.js",
diff --git a/ui/file_manager/audio_player/js/BUILD.gn b/ui/file_manager/audio_player/js/BUILD.gn
index 3485d29..e40980e0 100644
--- a/ui/file_manager/audio_player/js/BUILD.gn
+++ b/ui/file_manager/audio_player/js/BUILD.gn
@@ -61,7 +61,7 @@
     "//ui/file_manager/file_manager/common/js:mediasession_types.m",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/foreground/js/metadata:content_metadata_provider",
     "//ui/file_manager/file_manager/foreground/js/metadata:metadata_model",
     "//ui/webui/resources/js:load_time_data.m",
diff --git a/ui/file_manager/audio_player/js/audio_player.js b/ui/file_manager/audio_player/js/audio_player.js
index eb37bb8..650dad1 100644
--- a/ui/file_manager/audio_player/js/audio_player.js
+++ b/ui/file_manager/audio_player/js/audio_player.js
@@ -13,7 +13,7 @@
 import {MediaSessionPlaybackState} from '../../file_manager/common/js/mediasession_types.m.js';
 import {util} from '../../file_manager/common/js/util.m.js';
 import {AllowedPaths} from '../../file_manager/common/js/volume_manager_types.m.js';
-import {ExternallyUnmountedEvent} from '../../file_manager/externs/volume_manager.m.js';
+import {ExternallyUnmountedEvent} from '../../file_manager/externs/volume_manager.js';
 import {ContentMetadataProvider} from '../../file_manager/foreground/js/metadata/content_metadata_provider.js';
 import {MetadataModel} from '../../file_manager/foreground/js/metadata/metadata_model.js';
 
diff --git a/ui/file_manager/file_manager/BUILD.gn b/ui/file_manager/file_manager/BUILD.gn
index 3d8d88c..ebd51b596 100644
--- a/ui/file_manager/file_manager/BUILD.gn
+++ b/ui/file_manager/file_manager/BUILD.gn
@@ -32,6 +32,11 @@
     # For some unittests:
     "foreground/js/metadata/image_orientation.js",
     "externs/background/background_base.js",
+    "externs/entry_location.js",
+    "externs/files_app_entry_interfaces.js",
+    "externs/volume_info.js",
+    "externs/volume_info_list.js",
+    "externs/volume_manager.js",
 
     # CSS:
     "foreground/css/combobutton.css",
diff --git a/ui/file_manager/file_manager/background/js/BUILD.gn b/ui/file_manager/file_manager/background/js/BUILD.gn
index b5f4473b..5bd741b 100644
--- a/ui/file_manager/file_manager/background/js/BUILD.gn
+++ b/ui/file_manager/file_manager/background/js/BUILD.gn
@@ -151,8 +151,8 @@
     "//ui/file_manager/file_manager/common/js:metrics.m",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_info",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:crostini",
     "//ui/file_manager/file_manager/externs/background:drive_sync_handler",
     "//ui/file_manager/file_manager/externs/background:duplicate_finder",
@@ -185,7 +185,7 @@
   deps = [
     ":volume_manager_factory",
     "//ui/file_manager/file_manager/common/js:util.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:background_base",
     "//ui/webui/resources/js:assert.m",
     "//ui/webui/resources/js:load_time_data.m",
@@ -195,7 +195,7 @@
 js_library("crostini") {
   deps = [
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:crostini",
     "//ui/webui/resources/js:assert.m",
     "//ui/webui/resources/js:load_time_data.m",
@@ -220,8 +220,8 @@
     "//chrome/test/data/webui:chai_assert",
     "//ui/file_manager/file_manager/common/js:mock_entry.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:entry_location.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:entry_location",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:crostini",
     "//ui/webui/resources/js:load_time_data.m",
   ]
@@ -235,8 +235,8 @@
     "//ui/file_manager/file_manager/common/js:metrics.m",
     "//ui/file_manager/file_manager/common/js:progress_center_common.m",
     "//ui/file_manager/file_manager/common/js:util.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_info",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:progress_center",
     "//ui/webui/resources/js/cr:event_target.m",
   ]
@@ -254,14 +254,14 @@
     "//ui/file_manager/file_manager/common/js:mock_entry.m",
     "//ui/file_manager/file_manager/common/js:test_error_reporting.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
+    "//ui/file_manager/file_manager/externs:volume_info",
     "//ui/webui/resources/js:load_time_data.m",
   ]
 }
 
 js_library("mock_drive_sync_handler") {
   deps = [
-    "//ui/file_manager/file_manager/externs:drive_dialog_controller.m",
+    "//ui/file_manager/file_manager/externs:drive_dialog_controller",
     "//ui/file_manager/file_manager/externs/background:drive_sync_handler",
     "//ui/webui/resources/js/cr:event_target.m",
   ]
@@ -277,7 +277,7 @@
     "//ui/file_manager/file_manager/common/js:async_util.m",
     "//ui/file_manager/file_manager/common/js:progress_center_common.m",
     "//ui/file_manager/file_manager/common/js:util.m",
-    "//ui/file_manager/file_manager/externs:drive_dialog_controller.m",
+    "//ui/file_manager/file_manager/externs:drive_dialog_controller",
     "//ui/file_manager/file_manager/externs/background:drive_sync_handler",
     "//ui/file_manager/file_manager/externs/background:progress_center",
     "//ui/webui/resources/js/cr:event_target.m",
@@ -303,7 +303,7 @@
     "//ui/file_manager/file_manager/common/js:lru_cache.m",
     "//ui/file_manager/file_manager/common/js:metrics.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:duplicate_finder",
     "//ui/file_manager/file_manager/externs/background:import_history",
   ]
@@ -320,7 +320,7 @@
     "//ui/file_manager/file_manager/common/js:mock_entry.m",
     "//ui/file_manager/file_manager/common/js:test_error_reporting.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
+    "//ui/file_manager/file_manager/externs:volume_info",
     "//ui/file_manager/file_manager/externs/background:duplicate_finder",
   ]
 }
@@ -329,8 +329,8 @@
   deps = [
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:entry_location.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
+    "//ui/file_manager/file_manager/externs:entry_location",
+    "//ui/file_manager/file_manager/externs:volume_info",
   ]
 }
 
@@ -376,9 +376,9 @@
     "//ui/file_manager/file_manager/common/js:trash",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:xfm.m",
-    "//ui/file_manager/file_manager/externs:entry_location.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:entry_location",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:file_operation_manager",
     "//ui/webui/resources/js:assert.m",
   ]
@@ -395,7 +395,7 @@
     "//ui/file_manager/file_manager/common/js:mock_entry.m",
     "//ui/file_manager/file_manager/common/js:test_error_reporting.m",
     "//ui/file_manager/file_manager/common/js:util.m",
-    "//ui/file_manager/file_manager/externs:entry_location.m",
+    "//ui/file_manager/file_manager/externs:entry_location",
     "//ui/file_manager/file_manager/externs/background:file_operation_manager",
     "//ui/webui/resources/js:load_time_data.m",
   ]
@@ -498,7 +498,7 @@
     "//ui/file_manager/file_manager/common/js:test_error_reporting.m",
     "//ui/file_manager/file_manager/common/js:test_importer_common.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
+    "//ui/file_manager/file_manager/externs:volume_info",
     "//ui/file_manager/file_manager/externs/background:duplicate_finder",
     "//ui/file_manager/file_manager/externs/background:import_history",
     "//ui/file_manager/file_manager/externs/background:media_import_handler",
@@ -555,11 +555,11 @@
     "//ui/file_manager/file_manager/common/js:mock_entry.m",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:entry_location.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
-    "//ui/file_manager/file_manager/externs:volume_info_list.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:entry_location",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
+    "//ui/file_manager/file_manager/externs:volume_info",
+    "//ui/file_manager/file_manager/externs:volume_info_list",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/webui/resources/js:assert.m",
   ]
 }
@@ -578,7 +578,7 @@
     "//ui/file_manager/file_manager/common/js:async_util.m",
     "//ui/file_manager/file_manager/common/js:progress_center_common.m",
     "//ui/file_manager/file_manager/common/js:util.m",
-    "//ui/file_manager/file_manager/externs:progress_center_panel.m",
+    "//ui/file_manager/file_manager/externs:progress_center_panel",
     "//ui/file_manager/file_manager/externs/background:progress_center",
   ]
 }
@@ -606,8 +606,8 @@
     "//ui/file_manager/file_manager/common/js:files_app_entry_types.m",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
+    "//ui/file_manager/file_manager/externs:volume_info",
     "//ui/webui/resources/js:assert.m",
   ]
   visibility += [
@@ -668,7 +668,7 @@
   deps = [
     ":file_operation_util",
     "//ui/file_manager/file_manager/common/js:trash",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/webui/resources/js:assert.m",
     "//ui/webui/resources/js:load_time_data.m",
   ]
@@ -689,8 +689,8 @@
 
 js_library("volume_info_list_impl") {
   deps = [
-    "//ui/file_manager/file_manager/externs:volume_info.m",
-    "//ui/file_manager/file_manager/externs:volume_info_list.m",
+    "//ui/file_manager/file_manager/externs:volume_info",
+    "//ui/file_manager/file_manager/externs:volume_info_list",
     "//ui/webui/resources/js/cr/ui:array_data_model.m",
   ]
 }
@@ -717,8 +717,8 @@
     "//ui/file_manager/file_manager/common/js:async_util.m",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_info",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/webui/resources/js:assert.m",
     "//ui/webui/resources/js:cr.m",
     "//ui/webui/resources/js/cr:event_target.m",
@@ -728,7 +728,7 @@
 js_library("volume_manager_factory") {
   deps = [
     ":volume_manager_impl",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
   ]
 }
 
@@ -752,7 +752,7 @@
     ":volume_info_impl",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
+    "//ui/file_manager/file_manager/externs:volume_info",
   ]
 }
 
diff --git a/ui/file_manager/file_manager/background/js/background.js b/ui/file_manager/file_manager/background/js/background.js
index bfb6b74..834eeaf8 100644
--- a/ui/file_manager/file_manager/background/js/background.js
+++ b/ui/file_manager/file_manager/background/js/background.js
@@ -16,8 +16,8 @@
 import {mediaImportInterfaces} from '../../externs/background/media_import_handler.js';
 import {mediaScannerInterfaces} from '../../externs/background/media_scanner.js';
 import {ProgressCenter} from '../../externs/background/progress_center.js';
-import {VolumeInfo} from '../../externs/volume_info.m.js';
-import {VolumeManager} from '../../externs/volume_manager.m.js';
+import {VolumeInfo} from '../../externs/volume_info.js';
+import {VolumeManager} from '../../externs/volume_manager.js';
 
 import {BackgroundBaseImpl} from './background_base.js';
 import {CrostiniImpl} from './crostini.js';
diff --git a/ui/file_manager/file_manager/background/js/background_base.js b/ui/file_manager/file_manager/background/js/background_base.js
index 7c6f5ed..ed1e5b7bf 100644
--- a/ui/file_manager/file_manager/background/js/background_base.js
+++ b/ui/file_manager/file_manager/background/js/background_base.js
@@ -7,7 +7,7 @@
 
 import {util} from '../../common/js/util.m.js';
 import {BackgroundBase, LaunchHandler} from '../../externs/background/background_base.js';
-import {VolumeManager} from '../../externs/volume_manager.m.js';
+import {VolumeManager} from '../../externs/volume_manager.js';
 
 import {volumeManagerFactory} from './volume_manager_factory.js';
 
diff --git a/ui/file_manager/file_manager/background/js/crostini.js b/ui/file_manager/file_manager/background/js/crostini.js
index 3151014f..06eab07 100644
--- a/ui/file_manager/file_manager/background/js/crostini.js
+++ b/ui/file_manager/file_manager/background/js/crostini.js
@@ -7,7 +7,7 @@
 
 import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
 import {Crostini} from '../../externs/background/crostini.js';
-import {VolumeManager} from '../../externs/volume_manager.m.js';
+import {VolumeManager} from '../../externs/volume_manager.js';
 
 /**
  * Implementation of Crostini shared path state handler.
diff --git a/ui/file_manager/file_manager/background/js/crostini_unittest.m.js b/ui/file_manager/file_manager/background/js/crostini_unittest.m.js
index 4d3c758..a4bea2d 100644
--- a/ui/file_manager/file_manager/background/js/crostini_unittest.m.js
+++ b/ui/file_manager/file_manager/background/js/crostini_unittest.m.js
@@ -9,8 +9,8 @@
 import {MockDirectoryEntry, MockEntry, MockFileSystem} from '../../common/js/mock_entry.m.js';
 import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
 import {Crostini} from '../../externs/background/crostini.js';
-import {EntryLocation} from '../../externs/entry_location.m.js';
-import {VolumeManager} from '../../externs/volume_manager.m.js';
+import {EntryLocation} from '../../externs/entry_location.js';
+import {VolumeManager} from '../../externs/volume_manager.js';
 
 import {createCrostiniForTest} from './mock_crostini.js';
 
diff --git a/ui/file_manager/file_manager/background/js/device_handler.js b/ui/file_manager/file_manager/background/js/device_handler.js
index b0fd091..fecc3b8 100644
--- a/ui/file_manager/file_manager/background/js/device_handler.js
+++ b/ui/file_manager/file_manager/background/js/device_handler.js
@@ -11,8 +11,8 @@
 import {str, strf, util} from '../../common/js/util.m.js';
 import {xfm} from '../../common/js/xfm.m.js';
 import {ProgressCenter} from '../../externs/background/progress_center.js';
-import {VolumeInfo} from '../../externs/volume_info.m.js';
-import {VolumeManager} from '../../externs/volume_manager.m.js';
+import {VolumeInfo} from '../../externs/volume_info.js';
+import {VolumeManager} from '../../externs/volume_manager.js';
 
 import {volumeManagerFactory} from './volume_manager_factory.js';
 
diff --git a/ui/file_manager/file_manager/background/js/device_handler_unittest.m.js b/ui/file_manager/file_manager/background/js/device_handler_unittest.m.js
index 9a52c01d..e236abc 100644
--- a/ui/file_manager/file_manager/background/js/device_handler_unittest.m.js
+++ b/ui/file_manager/file_manager/background/js/device_handler_unittest.m.js
@@ -11,7 +11,7 @@
 import {MockFileSystem} from '../../common/js/mock_entry.m.js';
 import {reportPromise} from '../../common/js/test_error_reporting.m.js';
 import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
-import {VolumeInfo} from '../../externs/volume_info.m.js';
+import {VolumeInfo} from '../../externs/volume_info.js';
 
 import {DeviceHandler} from './device_handler.js';
 import {MockProgressCenter} from './mock_progress_center.js';
diff --git a/ui/file_manager/file_manager/background/js/drive_sync_handler.js b/ui/file_manager/file_manager/background/js/drive_sync_handler.js
index 600c424..6a57100 100644
--- a/ui/file_manager/file_manager/background/js/drive_sync_handler.js
+++ b/ui/file_manager/file_manager/background/js/drive_sync_handler.js
@@ -10,7 +10,7 @@
 import {xfm} from '../../common/js/xfm.m.js';
 import {DriveSyncHandler} from '../../externs/background/drive_sync_handler.js';
 import {ProgressCenter} from '../../externs/background/progress_center.js';
-import {DriveDialogControllerInterface} from '../../externs/drive_dialog_controller.m.js';
+import {DriveDialogControllerInterface} from '../../externs/drive_dialog_controller.js';
 
 import {fileOperationUtil} from './file_operation_util.js';
 import {launcher, LaunchType} from './launcher.js';
diff --git a/ui/file_manager/file_manager/background/js/duplicate_finder.js b/ui/file_manager/file_manager/background/js/duplicate_finder.js
index 2956ba1..f9ddc16 100644
--- a/ui/file_manager/file_manager/background/js/duplicate_finder.js
+++ b/ui/file_manager/file_manager/background/js/duplicate_finder.js
@@ -8,7 +8,7 @@
 import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
 import {duplicateFinderInterfaces} from '../../externs/background/duplicate_finder.js';
 import {importerHistoryInterfaces} from '../../externs/background/import_history.js';
-import {VolumeManager} from '../../externs/volume_manager.m.js';
+import {VolumeManager} from '../../externs/volume_manager.js';
 
 import {importerHistory} from './import_history.js';
 import {volumeManagerFactory} from './volume_manager_factory.js';
diff --git a/ui/file_manager/file_manager/background/js/duplicate_finder_unittest.m.js b/ui/file_manager/file_manager/background/js/duplicate_finder_unittest.m.js
index 1ce8ae36..13950f2 100644
--- a/ui/file_manager/file_manager/background/js/duplicate_finder_unittest.m.js
+++ b/ui/file_manager/file_manager/background/js/duplicate_finder_unittest.m.js
@@ -10,7 +10,7 @@
 import {reportPromise} from '../../common/js/test_error_reporting.m.js';
 import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
 import {duplicateFinderInterfaces} from '../../externs/background/duplicate_finder.js';
-import {VolumeInfo} from '../../externs/volume_info.m.js';
+import {VolumeInfo} from '../../externs/volume_info.js';
 
 import {duplicateFinder} from './duplicate_finder.js';
 import {MockVolumeManager} from './mock_volume_manager.js';
diff --git a/ui/file_manager/file_manager/background/js/entry_location_impl.js b/ui/file_manager/file_manager/background/js/entry_location_impl.js
index 83575c9..abaf3d4 100644
--- a/ui/file_manager/file_manager/background/js/entry_location_impl.js
+++ b/ui/file_manager/file_manager/background/js/entry_location_impl.js
@@ -4,8 +4,8 @@
 
 import {util} from '../../common/js/util.m.js';
 import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
-import {EntryLocation} from '../../externs/entry_location.m.js';
-import {VolumeInfo} from '../../externs/volume_info.m.js';
+import {EntryLocation} from '../../externs/entry_location.js';
+import {VolumeInfo} from '../../externs/volume_info.js';
 
 /**
  * Location information which shows where the path points in FileManager's
diff --git a/ui/file_manager/file_manager/background/js/file_operation_manager.js b/ui/file_manager/file_manager/background/js/file_operation_manager.js
index 96810b6..0b73b83 100644
--- a/ui/file_manager/file_manager/background/js/file_operation_manager.js
+++ b/ui/file_manager/file_manager/background/js/file_operation_manager.js
@@ -10,9 +10,9 @@
 import {util} from '../../common/js/util.m.js';
 import {xfm} from '../../common/js/xfm.m.js';
 import {FileOperationManager} from '../../externs/background/file_operation_manager.js';
-import {EntryLocation} from '../../externs/entry_location.m.js';
-import {FakeEntry} from '../../externs/files_app_entry_interfaces.m.js';
-import {VolumeManager} from '../../externs/volume_manager.m.js';
+import {EntryLocation} from '../../externs/entry_location.js';
+import {FakeEntry} from '../../externs/files_app_entry_interfaces.js';
+import {VolumeManager} from '../../externs/volume_manager.js';
 
 import {fileOperationUtil} from './file_operation_util.js';
 import {metadataProxy} from './metadata_proxy.js';
diff --git a/ui/file_manager/file_manager/background/js/file_operation_manager_unittest.m.js b/ui/file_manager/file_manager/background/js/file_operation_manager_unittest.m.js
index d0b5c98c..84e7413 100644
--- a/ui/file_manager/file_manager/background/js/file_operation_manager_unittest.m.js
+++ b/ui/file_manager/file_manager/background/js/file_operation_manager_unittest.m.js
@@ -12,7 +12,7 @@
 import {reportPromise, waitUntil} from '../../common/js/test_error_reporting.m.js';
 import {util} from '../../common/js/util.m.js';
 import {FileOperationManager} from '../../externs/background/file_operation_manager.js';
-import {EntryLocation} from '../../externs/entry_location.m.js';
+import {EntryLocation} from '../../externs/entry_location.js';
 
 import {FileOperationManagerImpl} from './file_operation_manager.js';
 import {fileOperationUtil} from './file_operation_util.js';
diff --git a/ui/file_manager/file_manager/background/js/media_import_handler_unittest.m.js b/ui/file_manager/file_manager/background/js/media_import_handler_unittest.m.js
index dc465ec..07922e13 100644
--- a/ui/file_manager/file_manager/background/js/media_import_handler_unittest.m.js
+++ b/ui/file_manager/file_manager/background/js/media_import_handler_unittest.m.js
@@ -14,7 +14,7 @@
 import {duplicateFinderInterfaces} from '../../externs/background/duplicate_finder.js';
 import {importerHistoryInterfaces} from '../../externs/background/import_history.js';
 import {mediaImportInterfaces} from '../../externs/background/media_import_handler.js';
-import {VolumeInfo} from '../../externs/volume_info.m.js';
+import {VolumeInfo} from '../../externs/volume_info.js';
 
 import {fileOperationUtil} from './file_operation_util.js';
 import {mediaImport} from './media_import_handler.js';
diff --git a/ui/file_manager/file_manager/background/js/mock_drive_sync_handler.js b/ui/file_manager/file_manager/background/js/mock_drive_sync_handler.js
index 6c427e1..9d0e169 100644
--- a/ui/file_manager/file_manager/background/js/mock_drive_sync_handler.js
+++ b/ui/file_manager/file_manager/background/js/mock_drive_sync_handler.js
@@ -5,7 +5,7 @@
 import {NativeEventTarget as EventTarget} from 'chrome://resources/js/cr/event_target.m.js';
 
 import {DriveSyncHandler} from '../../externs/background/drive_sync_handler.js';
-import {DriveDialogControllerInterface} from '../../externs/drive_dialog_controller.m.js';
+import {DriveDialogControllerInterface} from '../../externs/drive_dialog_controller.js';
 
 
 /**
diff --git a/ui/file_manager/file_manager/background/js/mock_volume_manager.js b/ui/file_manager/file_manager/background/js/mock_volume_manager.js
index 6697472..5e44bfd 100644
--- a/ui/file_manager/file_manager/background/js/mock_volume_manager.js
+++ b/ui/file_manager/file_manager/background/js/mock_volume_manager.js
@@ -7,11 +7,11 @@
 import {MockEntry, MockFileSystem} from '../../common/js/mock_entry.m.js';
 import {str, util} from '../../common/js/util.m.js';
 import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
-import {EntryLocation} from '../../externs/entry_location.m.js';
-import {FakeEntry, FilesAppEntry} from '../../externs/files_app_entry_interfaces.m.js';
-import {VolumeInfo} from '../../externs/volume_info.m.js';
-import {VolumeInfoList} from '../../externs/volume_info_list.m.js';
-import {VolumeManager} from '../../externs/volume_manager.m.js';
+import {EntryLocation} from '../../externs/entry_location.js';
+import {FakeEntry, FilesAppEntry} from '../../externs/files_app_entry_interfaces.js';
+import {VolumeInfo} from '../../externs/volume_info.js';
+import {VolumeInfoList} from '../../externs/volume_info_list.js';
+import {VolumeManager} from '../../externs/volume_manager.js';
 
 import {EntryLocationImpl} from './entry_location_impl.js';
 import {VolumeInfoImpl} from './volume_info_impl.js';
diff --git a/ui/file_manager/file_manager/background/js/progress_center.js b/ui/file_manager/file_manager/background/js/progress_center.js
index 4d74eac..840fbc6 100644
--- a/ui/file_manager/file_manager/background/js/progress_center.js
+++ b/ui/file_manager/file_manager/background/js/progress_center.js
@@ -7,7 +7,7 @@
 import {str} from '../../common/js/util.m.js';
 import {xfm} from '../../common/js/xfm.m.js';
 import {ProgressCenter} from '../../externs/background/progress_center.js';
-import {ProgressCenterPanelInterface} from '../../externs/progress_center_panel.m.js';
+import {ProgressCenterPanelInterface} from '../../externs/progress_center_panel.js';
 
 /**
  * Implementation of {ProgressCenter} at the background page.
diff --git a/ui/file_manager/file_manager/background/js/trash.js b/ui/file_manager/file_manager/background/js/trash.js
index bd87df9..8464ced 100644
--- a/ui/file_manager/file_manager/background/js/trash.js
+++ b/ui/file_manager/file_manager/background/js/trash.js
@@ -11,7 +11,7 @@
 import {loadTimeData} from 'chrome://resources/js/load_time_data.m.js';
 
 import {TrashConfig, TrashDirs, TrashEntry} from '../../common/js/trash.js';
-import {VolumeManager} from '../../externs/volume_manager.m.js';
+import {VolumeManager} from '../../externs/volume_manager.js';
 
 import {fileOperationUtil} from './file_operation_util.js';
 
diff --git a/ui/file_manager/file_manager/background/js/volume_info_impl.js b/ui/file_manager/file_manager/background/js/volume_info_impl.js
index 1623027..0ecb5ac 100644
--- a/ui/file_manager/file_manager/background/js/volume_info_impl.js
+++ b/ui/file_manager/file_manager/background/js/volume_info_impl.js
@@ -7,8 +7,8 @@
 import {FakeEntryImpl} from '../../common/js/files_app_entry_types.m.js';
 import {str} from '../../common/js/util.m.js';
 import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
-import {FakeEntry, FilesAppEntry} from '../../externs/files_app_entry_interfaces.m.js';
-import {VolumeInfo} from '../../externs/volume_info.m.js';
+import {FakeEntry, FilesAppEntry} from '../../externs/files_app_entry_interfaces.js';
+import {VolumeInfo} from '../../externs/volume_info.js';
 
 /**
  * Represents each volume, such as "drive", "download directory", each "USB
diff --git a/ui/file_manager/file_manager/background/js/volume_info_list_impl.js b/ui/file_manager/file_manager/background/js/volume_info_list_impl.js
index fe34fb6b..60a5a63 100644
--- a/ui/file_manager/file_manager/background/js/volume_info_list_impl.js
+++ b/ui/file_manager/file_manager/background/js/volume_info_list_impl.js
@@ -4,8 +4,8 @@
 
 import {ArrayDataModel} from 'chrome://resources/js/cr/ui/array_data_model.m.js';
 
-import {VolumeInfo} from '../../externs/volume_info.m.js';
-import {VolumeInfoList} from '../../externs/volume_info_list.m.js';
+import {VolumeInfo} from '../../externs/volume_info.js';
+import {VolumeInfoList} from '../../externs/volume_info_list.js';
 
 /**
  * The container of the VolumeInfo for each mounted volume.
diff --git a/ui/file_manager/file_manager/background/js/volume_manager_factory.js b/ui/file_manager/file_manager/background/js/volume_manager_factory.js
index a2749795..cc2c892 100644
--- a/ui/file_manager/file_manager/background/js/volume_manager_factory.js
+++ b/ui/file_manager/file_manager/background/js/volume_manager_factory.js
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import {VolumeManager} from '../../externs/volume_manager.m.js';
+import {VolumeManager} from '../../externs/volume_manager.js';
 
 import {VolumeManagerImpl} from './volume_manager_impl.js';
 
diff --git a/ui/file_manager/file_manager/background/js/volume_manager_impl.js b/ui/file_manager/file_manager/background/js/volume_manager_impl.js
index 48e3ebd..41a869b 100644
--- a/ui/file_manager/file_manager/background/js/volume_manager_impl.js
+++ b/ui/file_manager/file_manager/background/js/volume_manager_impl.js
@@ -9,8 +9,8 @@
 import {AsyncUtil} from '../../common/js/async_util.m.js';
 import {util} from '../../common/js/util.m.js';
 import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
-import {VolumeInfo} from '../../externs/volume_info.m.js';
-import {VolumeManager} from '../../externs/volume_manager.m.js';
+import {VolumeInfo} from '../../externs/volume_info.js';
+import {VolumeManager} from '../../externs/volume_manager.js';
 
 import {EntryLocationImpl} from './entry_location_impl.js';
 import {VolumeInfoListImpl} from './volume_info_list_impl.js';
diff --git a/ui/file_manager/file_manager/background/js/volume_manager_util.js b/ui/file_manager/file_manager/background/js/volume_manager_util.js
index 5f1675f4..430cab1 100644
--- a/ui/file_manager/file_manager/background/js/volume_manager_util.js
+++ b/ui/file_manager/file_manager/background/js/volume_manager_util.js
@@ -4,7 +4,7 @@
 
 import {str, util} from '../../common/js/util.m.js';
 import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
-import {VolumeInfo} from '../../externs/volume_info.m.js';
+import {VolumeInfo} from '../../externs/volume_info.js';
 
 import {VolumeInfoImpl} from './volume_info_impl.js';
 
diff --git a/ui/file_manager/file_manager/common/js/BUILD.gn b/ui/file_manager/file_manager/common/js/BUILD.gn
index 4f529d1..e9fd9f38 100644
--- a/ui/file_manager/file_manager/common/js/BUILD.gn
+++ b/ui/file_manager/file_manager/common/js/BUILD.gn
@@ -70,15 +70,17 @@
   ]
 
   closure_flags =
-      strict_error_checking_closure_args +
-      [ "browser_resolver_prefix_replacements=\"chrome://test/=./\"" ]
+      strict_error_checking_closure_args + [
+        "js_module_root=./gen/ui",
+        "js_module_root=../../ui",
+        "browser_resolver_prefix_replacements=\"chrome://test/=./\"",
+      ]
 }
 
 js_library("app_util") {
   deps = [
     ":volume_manager_types",
     ":xfm",
-    "//ui/file_manager/file_manager/externs:volume_manager",
   ]
   externs_list = [
     "//ui/file_manager/file_manager/externs/app_window_common.js",
@@ -91,7 +93,7 @@
       [ "$root_gen_dir/ui/file_manager/file_manager/common/js/app_util.m.js" ]
   deps = [
     "//ui/file_manager/file_manager/externs:file_manager_private",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:background_base",
   ]
   externs_list =
@@ -135,7 +137,7 @@
     ":mock_entry.m",
     "//chrome/test/data/webui:chai_assert",
     "//ui/file_manager/file_manager/common/js:test_error_reporting.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
+    "//ui/file_manager/file_manager/externs:volume_info",
     "//ui/webui/resources/js:assert.m",
   ]
 }
@@ -144,7 +146,7 @@
   sources = [ "$root_gen_dir/ui/file_manager/file_manager/common/js/files_app_entry_types.m.js" ]
   deps = [
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
+    "//ui/file_manager/file_manager/externs:volume_info",
   ]
 
   extra_deps = [ ":modulize" ]
@@ -163,7 +165,7 @@
   deps = [
     ":files_app_entry_types.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
     "//ui/webui/resources/js:assert.m",
   ]
 
@@ -189,7 +191,7 @@
   sources = [ "$root_gen_dir/ui/file_manager/file_manager/common/js/file_operation_common.m.js" ]
   deps = [
     ":util.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
   ]
 
   extra_deps = [ ":modulize" ]
@@ -201,7 +203,6 @@
     "//ui/file_manager/file_manager/common/js:files_app_entry_types",
     "//ui/file_manager/file_manager/common/js:volume_manager_types",
     "//ui/file_manager/file_manager/externs:file_manager_private",
-    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/webui/resources/js:cr",
     "//ui/webui/resources/js/cr/ui:array_data_model",
   ]
@@ -213,11 +214,11 @@
   deps = [
     "//ui/file_manager/file_manager/common/js:files_app_entry_types.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:entry_location.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
-    "//ui/file_manager/file_manager/externs:volume_info_list.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:entry_location",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
+    "//ui/file_manager/file_manager/externs:volume_info",
+    "//ui/file_manager/file_manager/externs:volume_info_list",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/webui/resources/js:assert.m",
     "//ui/webui/resources/js:cr.m",
     "//ui/webui/resources/js/cr:event_target.m",
@@ -237,7 +238,6 @@
     ":file_type",
     ":xfm",
     "//ui/file_manager/file_manager/common/js:volume_manager_types",
-    "//ui/file_manager/file_manager/externs:volume_manager",
   ]
 }
 
@@ -248,9 +248,9 @@
   deps = [
     ":file_type.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
+    "//ui/file_manager/file_manager/externs:volume_info",
+    "//ui/file_manager/file_manager/externs:volume_manager",
   ]
 
   extra_deps = [ ":modulize" ]
@@ -288,7 +288,7 @@
     "//ui/file_manager/file_manager/common/js:mock_chrome.m",
     "//ui/file_manager/file_manager/common/js:test_error_reporting.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
+    "//ui/file_manager/file_manager/externs:volume_info",
   ]
 }
 
@@ -451,8 +451,8 @@
     ":files_app_entry_types.m",
     ":util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/webui/resources/js:assert.m",
   ]
 }
@@ -507,11 +507,11 @@
     ":files_app_entry_types.m",
     "//ui/file_manager/file_manager/common/js:files_app_entry_types.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:entry_location.m",
+    "//ui/file_manager/file_manager/externs:entry_location",
     "//ui/file_manager/file_manager/externs:file_manager_private",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
+    "//ui/file_manager/file_manager/externs:volume_info",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/webui/resources/js:assert.m",
     "//ui/webui/resources/js:load_time_data.m",
     "//ui/webui/resources/js:util.m",
diff --git a/ui/file_manager/file_manager/common/js/app_util.js b/ui/file_manager/file_manager/common/js/app_util.js
index 0525d66..0bc4149 100644
--- a/ui/file_manager/file_manager/common/js/app_util.js
+++ b/ui/file_manager/file_manager/common/js/app_util.js
@@ -10,7 +10,7 @@
 
 // clang-format off
 // #import {BackgroundBase} from '../../externs/background/background_base.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {xfm} from './xfm.m.js';
 // clang-format on
 
diff --git a/ui/file_manager/file_manager/common/js/file_operation_common.js b/ui/file_manager/file_manager/common/js/file_operation_common.js
index 58dbe956..6381308 100644
--- a/ui/file_manager/file_manager/common/js/file_operation_common.js
+++ b/ui/file_manager/file_manager/common/js/file_operation_common.js
@@ -4,7 +4,7 @@
 
 // clang-format off
 // #import {util} from './util.m.js';
-// #import {FilesAppEntry} from '../../externs/files_app_entry_interfaces.m.js'
+// #import {FilesAppEntry} from '../../externs/files_app_entry_interfaces.js'
 // clang-format on
 
 /* #export */ class FileOperationProgressEvent extends Event {
diff --git a/ui/file_manager/file_manager/common/js/file_type.js b/ui/file_manager/file_manager/common/js/file_type.js
index f47cb39..dea7e67 100644
--- a/ui/file_manager/file_manager/common/js/file_type.js
+++ b/ui/file_manager/file_manager/common/js/file_type.js
@@ -4,7 +4,7 @@
 
 // clang-format off
 // #import * as wrappedVolumeManagerCommon from './volume_manager_types.m.js'; const {VolumeManagerCommon} = wrappedVolumeManagerCommon;
-// #import {FilesAppEntry} from '../../externs/files_app_entry_interfaces.m.js';
+// #import {FilesAppEntry} from '../../externs/files_app_entry_interfaces.js';
 // #import {VolumeEntry} from './files_app_entry_types.m.js';
 // #import {assert} from 'chrome://resources/js/assert.m.js';
 // clang-format on
diff --git a/ui/file_manager/file_manager/common/js/files_app_entry_types.js b/ui/file_manager/file_manager/common/js/files_app_entry_types.js
index d6686a5..f9c5823 100644
--- a/ui/file_manager/file_manager/common/js/files_app_entry_types.js
+++ b/ui/file_manager/file_manager/common/js/files_app_entry_types.js
@@ -23,8 +23,8 @@
 
 // clang-format off
 // #import * as wrappedVolumeManagerCommon from './volume_manager_types.m.js'; const {VolumeManagerCommon} = wrappedVolumeManagerCommon;
-// #import {FilesAppEntry, FilesAppDirEntry, FakeEntry} from '../../externs/files_app_entry_interfaces.m.js';
-// #import {VolumeInfo} from '../../externs/volume_info.m.js';
+// #import {FilesAppEntry, FilesAppDirEntry, FakeEntry} from '../../externs/files_app_entry_interfaces.js';
+// #import {VolumeInfo} from '../../externs/volume_info.js';
 // clang-format on
 
 /**
diff --git a/ui/file_manager/file_manager/common/js/files_app_entry_types_unittest.m.js b/ui/file_manager/file_manager/common/js/files_app_entry_types_unittest.m.js
index d4ab2c9c..38f51af 100644
--- a/ui/file_manager/file_manager/common/js/files_app_entry_types_unittest.m.js
+++ b/ui/file_manager/file_manager/common/js/files_app_entry_types_unittest.m.js
@@ -12,7 +12,7 @@
 import {MockFileSystem} from './mock_entry.m.js';
 import {reportPromise, waitUntil} from './test_error_reporting.m.js';
 import {VolumeEntry, EntryList, StaticReader, CombinedReaders, FakeEntryImpl} from './files_app_entry_types.m.js';
-import {VolumeInfo} from '../../externs/volume_info.m.js';
+import {VolumeInfo} from '../../externs/volume_info.js';
 // clang-format on
 
 
diff --git a/ui/file_manager/file_manager/common/js/filtered_volume_manager.js b/ui/file_manager/file_manager/common/js/filtered_volume_manager.js
index 478bbc4..dc49367 100644
--- a/ui/file_manager/file_manager/common/js/filtered_volume_manager.js
+++ b/ui/file_manager/file_manager/common/js/filtered_volume_manager.js
@@ -4,11 +4,11 @@
 
 // clang-format off
 // #import {assert} from 'chrome://resources/js/assert.m.js';
-// #import {VolumeInfo} from '../../externs/volume_info.m.js';
-// #import {VolumeInfoList} from '../../externs/volume_info_list.m.js';
-// #import {VolumeManager, ExternallyUnmountedEvent} from '../../externs/volume_manager.m.js';
-// #import {FilesAppEntry} from '../../externs/files_app_entry_interfaces.m.js';
-// #import {EntryLocation} from '../../externs/entry_location.m.js';
+// #import {VolumeInfo} from '../../externs/volume_info.js';
+// #import {VolumeInfoList} from '../../externs/volume_info_list.js';
+// #import {VolumeManager, ExternallyUnmountedEvent} from '../../externs/volume_manager.js';
+// #import {FilesAppEntry} from '../../externs/files_app_entry_interfaces.js';
+// #import {EntryLocation} from '../../externs/entry_location.js';
 // #import {VolumeManagerCommon, AllowedPaths} from './volume_manager_types.m.js';
 // #import {dispatchSimpleEvent} from 'chrome://resources/js/cr.m.js';
 // #import {ArrayDataModel} from 'chrome://resources/js/cr/ui/array_data_model.m.js';
diff --git a/ui/file_manager/file_manager/common/js/importer_common.js b/ui/file_manager/file_manager/common/js/importer_common.js
index 4731debd..97f076ad 100644
--- a/ui/file_manager/file_manager/common/js/importer_common.js
+++ b/ui/file_manager/file_manager/common/js/importer_common.js
@@ -8,9 +8,9 @@
  */
 
 // clang-format off
-// #import {FilesAppEntry} from '../../externs/files_app_entry_interfaces.m.js';
-// #import {VolumeInfo} from '../../externs/volume_info.m.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {FilesAppEntry} from '../../externs/files_app_entry_interfaces.js';
+// #import {VolumeInfo} from '../../externs/volume_info.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {FileType} from './file_type.m.js';
 // #import {VolumeManagerCommon} from './volume_manager_types.m.js';
 // #import {xfm} from './xfm.m.js';
diff --git a/ui/file_manager/file_manager/common/js/importer_common_unittest.m.js b/ui/file_manager/file_manager/common/js/importer_common_unittest.m.js
index acc72ad..f63411ef 100644
--- a/ui/file_manager/file_manager/common/js/importer_common_unittest.m.js
+++ b/ui/file_manager/file_manager/common/js/importer_common_unittest.m.js
@@ -5,7 +5,7 @@
 import {assertEquals, assertFalse, assertTrue} from 'chrome://test/chai_assert.js';
 
 import {MockVolumeManager} from '../../background/js/mock_volume_manager.js';
-import {VolumeInfo} from '../../externs/volume_info.m.js';
+import {VolumeInfo} from '../../externs/volume_info.js';
 
 import {importer} from './importer_common.m.js';
 import {MockChromeStorageAPI, MockCommandLinePrivate} from './mock_chrome.m.js';
diff --git a/ui/file_manager/file_manager/common/js/trash.js b/ui/file_manager/file_manager/common/js/trash.js
index 26e015d..2f64ed25 100644
--- a/ui/file_manager/file_manager/common/js/trash.js
+++ b/ui/file_manager/file_manager/common/js/trash.js
@@ -21,8 +21,8 @@
 
 import {assert} from 'chrome://resources/js/assert.m.js';
 
-import {FilesAppEntry} from '../../externs/files_app_entry_interfaces.m.js';
-import {VolumeManager} from '../../externs/volume_manager.m.js';
+import {FilesAppEntry} from '../../externs/files_app_entry_interfaces.js';
+import {VolumeManager} from '../../externs/volume_manager.js';
 
 import {CombinedReaders, FakeEntryImpl} from './files_app_entry_types.m.js';
 import {str, util} from './util.m.js';
diff --git a/ui/file_manager/file_manager/common/js/util.js b/ui/file_manager/file_manager/common/js/util.js
index f7b6c87..5a092c6 100644
--- a/ui/file_manager/file_manager/common/js/util.js
+++ b/ui/file_manager/file_manager/common/js/util.js
@@ -15,11 +15,11 @@
 // #import {assert} from 'chrome://resources/js/assert.m.js';
 // #import * as wrappedVolumeManagerCommon from './volume_manager_types.m.js'; const {VolumeManagerCommon} = wrappedVolumeManagerCommon;
 // #import {decorate} from 'chrome://resources/js/cr/ui.m.js';
-// #import {FilesAppEntry, FakeEntry} from '../../externs/files_app_entry_interfaces.m.js';
+// #import {FilesAppEntry, FakeEntry} from '../../externs/files_app_entry_interfaces.js';
 // #import {EntryList} from './files_app_entry_types.m.js';
-// #import {VolumeInfo} from '../../externs/volume_info.m.js';
-// #import {EntryLocation} from '../../externs/entry_location.m.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeInfo} from '../../externs/volume_info.js';
+// #import {EntryLocation} from '../../externs/entry_location.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // clang-format on
 
 /**
diff --git a/ui/file_manager/file_manager/externs/BUILD.gn b/ui/file_manager/file_manager/externs/BUILD.gn
index 654da59..f208ed67 100644
--- a/ui/file_manager/file_manager/externs/BUILD.gn
+++ b/ui/file_manager/file_manager/externs/BUILD.gn
@@ -3,7 +3,6 @@
 # found in the LICENSE file.
 
 import("//third_party/closure_compiler/compile_js.gni")
-import("//ui/webui/resources/tools/js_modulizer.gni")
 
 js_library("file_manager_private") {
   sources = []
@@ -18,21 +17,14 @@
   ]
 }
 
-js_library("background_window.m") {
-  sources = [
-    "$root_gen_dir/ui/file_manager/file_manager/externs/background_window.m.js",
-  ]
-
+js_library("background_window") {
   deps = [ "//ui/file_manager/file_manager/externs/background:background_base" ]
-
-  extra_deps = [ ":modulize" ]
 }
 
-js_library("command_handler_deps.m") {
-  sources = [ "$root_gen_dir/ui/file_manager/file_manager/externs/command_handler_deps.m.js" ]
+js_library("command_handler_deps") {
   deps = [
-    ":files_app_entry_interfaces.m",
-    ":volume_manager.m",
+    ":files_app_entry_interfaces",
+    ":volume_manager",
     "background:crostini",
     "background:file_operation_manager",
     "background:progress_center",
@@ -51,143 +43,59 @@
     "//ui/file_manager/file_manager/foreground/js/ui:directory_tree",
     "//ui/file_manager/file_manager/foreground/js/ui:file_manager_ui",
   ]
-
-  extra_deps = [ ":modulize" ]
 }
 
-js_library("directory_change_event.m") {
-  sources = [ "$root_gen_dir/ui/file_manager/file_manager/externs/directory_change_event.m.js" ]
-  deps = [ ":files_app_entry_interfaces.m" ]
-
-  extra_deps = [ ":modulize" ]
+js_library("directory_change_event") {
+  deps = [ ":files_app_entry_interfaces" ]
 }
 
-js_library("drive_dialog_controller.m") {
-  sources = [ "$root_gen_dir/ui/file_manager/file_manager/externs/drive_dialog_controller.m.js" ]
-
-  extra_deps = [ ":modulize" ]
+js_library("drive_dialog_controller") {
 }
 
-js_library("entries_changed_event.m") {
-  sources = [ "$root_gen_dir/ui/file_manager/file_manager/externs/entries_changed_event.m.js" ]
-
+js_library("entries_changed_event") {
   deps = [ "//ui/file_manager/file_manager/common/js:util.m" ]
-
-  extra_deps = [ ":modulize" ]
 }
 
-js_library("entry_location.m") {
-  sources = [
-    "$root_gen_dir/ui/file_manager/file_manager/externs/entry_location.m.js",
-  ]
-
+js_library("entry_location") {
   deps = [
-    ":volume_info.m",
+    ":volume_info",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
   ]
-
-  extra_deps = [ ":modulize" ]
 }
 
-js_library("exif_entry.m") {
-  sources =
-      [ "$root_gen_dir/ui/file_manager/file_manager/externs/exif_entry.m.js" ]
-
+js_library("exif_entry") {
   deps =
       [ "//ui/file_manager/file_manager/foreground/js/metadata:exif_constants" ]
-
-  extra_deps = [ ":modulize" ]
 }
 
-js_library("files_app_entry_interfaces.m") {
-  sources = [ "$root_gen_dir/ui/file_manager/file_manager/externs/files_app_entry_interfaces.m.js" ]
-
+js_library("files_app_entry_interfaces") {
   deps = [ "//ui/file_manager/file_manager/common/js:volume_manager_types.m" ]
-
-  extra_deps = [ ":modulize" ]
 }
 
-js_library("metadata_worker_window.m") {
-  sources = [ "$root_gen_dir/ui/file_manager/file_manager/externs/metadata_worker_window.m.js" ]
-
-  extra_deps = [ ":modulize" ]
+js_library("metadata_worker_window") {
 }
 
-js_library("progress_center_panel.m") {
-  sources = [ "$root_gen_dir/ui/file_manager/file_manager/externs/progress_center_panel.m.js" ]
-
+js_library("progress_center_panel") {
   deps = [ "//ui/file_manager/file_manager/common/js:progress_center_common.m" ]
-  extra_deps = [ ":modulize" ]
 }
 
 js_library("volume_manager") {
-  sources = []
-
-  # Encapsulate volume_manager.js and its dependencies. Note this should really
-  # depend on volume_manager_types.js as well, but that's not an extern.
-  externs_list = [
-    "entry_location.js",
-    "files_app_entry_interfaces.js",
-    "volume_info.js",
-    "volume_info_list.js",
-    "volume_manager.js",
-  ]
-}
-
-js_library("volume_manager.m") {
-  sources = [
-    "$root_gen_dir/ui/file_manager/file_manager/externs/volume_manager.m.js",
-  ]
-
   deps = [
-    ":entry_location.m",
-    ":files_app_entry_interfaces.m",
-    ":volume_info.m",
-    ":volume_info_list.m",
+    ":entry_location",
+    ":files_app_entry_interfaces",
+    ":volume_info",
+    ":volume_info_list",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
   ]
-
-  extra_deps = [ ":modulize" ]
 }
 
-js_library("volume_info.m") {
-  sources =
-      [ "$root_gen_dir/ui/file_manager/file_manager/externs/volume_info.m.js" ]
-
+js_library("volume_info") {
   deps = [
-    ":files_app_entry_interfaces.m",
+    ":files_app_entry_interfaces",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
   ]
-
-  extra_deps = [ ":modulize" ]
 }
 
-js_library("volume_info_list.m") {
-  sources = [
-    "$root_gen_dir/ui/file_manager/file_manager/externs/volume_info_list.m.js",
-  ]
-
-  deps = [ ":volume_info.m" ]
-
-  extra_deps = [ ":modulize" ]
-}
-
-js_modulizer("modulize") {
-  input_files = [
-    "background_window.js",
-    "command_handler_deps.js",
-    "directory_change_event.js",
-    "drive_dialog_controller.js",
-    "entries_changed_event.js",
-    "entry_location.js",
-    "exif_entry.js",
-    "files_app_entry_interfaces.js",
-    "metadata_worker_window.js",
-    "progress_center_panel.js",
-    "volume_info.js",
-    "volume_info_list.js",
-    "volume_manager.js",
-  ]
-
-  preserve_offsets = [ "True" ]
+js_library("volume_info_list") {
+  deps = [ ":volume_info" ]
 }
diff --git a/ui/file_manager/file_manager/externs/background/BUILD.gn b/ui/file_manager/file_manager/externs/background/BUILD.gn
index d8098e1..fdfc3153 100644
--- a/ui/file_manager/file_manager/externs/background/BUILD.gn
+++ b/ui/file_manager/file_manager/externs/background/BUILD.gn
@@ -34,11 +34,11 @@
 }
 
 js_library("background_base") {
-  deps = [ "..:volume_manager.m" ]
+  deps = [ "..:volume_manager" ]
 }
 
 js_library("drive_sync_handler") {
-  deps = [ "..:drive_dialog_controller.m" ]
+  deps = [ "..:drive_dialog_controller" ]
 }
 
 js_library("duplicate_finder") {
@@ -49,13 +49,13 @@
 }
 
 js_library("crostini") {
-  deps = [ "..:volume_manager.m" ]
+  deps = [ "..:volume_manager" ]
 }
 
 js_library("file_operation_manager") {
   deps = [
-    "..:files_app_entry_interfaces.m",
-    "..:volume_manager.m",
+    "..:files_app_entry_interfaces",
+    "..:volume_manager",
   ]
 }
 
@@ -81,7 +81,7 @@
 
 js_library("progress_center") {
   deps = [
-    "..:progress_center_panel.m",
+    "..:progress_center_panel",
     "//ui/file_manager/file_manager/common/js:progress_center_common.m",
   ]
 }
diff --git a/ui/file_manager/file_manager/externs/background/background_base.js b/ui/file_manager/file_manager/externs/background/background_base.js
index c9c1caa..66a4230 100644
--- a/ui/file_manager/file_manager/externs/background/background_base.js
+++ b/ui/file_manager/file_manager/externs/background/background_base.js
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import {VolumeManager} from '../volume_manager.m.js';
+import {VolumeManager} from '../volume_manager.js';
 
 /** @typedef {function(!Array<string>):!Promise} */
 export let LaunchHandler;
diff --git a/ui/file_manager/file_manager/externs/background/crostini.js b/ui/file_manager/file_manager/externs/background/crostini.js
index 7d47f01..67555c9 100644
--- a/ui/file_manager/file_manager/externs/background/crostini.js
+++ b/ui/file_manager/file_manager/externs/background/crostini.js
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import {VolumeManager} from '../volume_manager.m.js';
+import {VolumeManager} from '../volume_manager.js';
 
 /**
  * Crostini shared path state handler.
diff --git a/ui/file_manager/file_manager/externs/background/drive_sync_handler.js b/ui/file_manager/file_manager/externs/background/drive_sync_handler.js
index 35492ef7..0c4caa5f 100644
--- a/ui/file_manager/file_manager/externs/background/drive_sync_handler.js
+++ b/ui/file_manager/file_manager/externs/background/drive_sync_handler.js
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import {DriveDialogControllerInterface} from '../drive_dialog_controller.m.js';
+import {DriveDialogControllerInterface} from '../drive_dialog_controller.js';
 
 /**
  * Handler of the background page for the Drive sync events. Implementations
diff --git a/ui/file_manager/file_manager/externs/background/file_operation_manager.js b/ui/file_manager/file_manager/externs/background/file_operation_manager.js
index bc6f60cca..d04e70fde 100644
--- a/ui/file_manager/file_manager/externs/background/file_operation_manager.js
+++ b/ui/file_manager/file_manager/externs/background/file_operation_manager.js
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import {FakeEntry, FilesAppEntry} from '../files_app_entry_interfaces.m.js';
-import {VolumeManager} from '../volume_manager.m.js';
+import {FakeEntry, FilesAppEntry} from '../files_app_entry_interfaces.js';
+import {VolumeManager} from '../volume_manager.js';
 
 /**
  * FileOperationManager: manager of file operations. Implementations of this
diff --git a/ui/file_manager/file_manager/externs/background/progress_center.js b/ui/file_manager/file_manager/externs/background/progress_center.js
index faa94bb0..d9b98b6 100644
--- a/ui/file_manager/file_manager/externs/background/progress_center.js
+++ b/ui/file_manager/file_manager/externs/background/progress_center.js
@@ -3,7 +3,7 @@
 // found in the LICENSE file.
 
 import {ProgressCenterItem} from '../../common/js/progress_center_common.m.js';
-import {ProgressCenterPanelInterface} from '../progress_center_panel.m.js';
+import {ProgressCenterPanelInterface} from '../progress_center_panel.js';
 
 /**
  * Progress center at the background page.
diff --git a/ui/file_manager/file_manager/externs/background_window.js b/ui/file_manager/file_manager/externs/background_window.js
index 5a61a146..c714d01 100644
--- a/ui/file_manager/file_manager/externs/background_window.js
+++ b/ui/file_manager/file_manager/externs/background_window.js
@@ -2,12 +2,12 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// #import {BackgroundBase} from './background/background_base.js';
+import {BackgroundBase} from './background/background_base.js';
 
 /**
  * @extends {Window}
  */
-/* #export */ class BackgroundWindow {
+export class BackgroundWindow {
   constructor() {
     /**
      * For File Manager it uses FileBrowserBackgroundFull.
diff --git a/ui/file_manager/file_manager/externs/command_handler_deps.js b/ui/file_manager/file_manager/externs/command_handler_deps.js
index 6094078..b776ce15 100644
--- a/ui/file_manager/file_manager/externs/command_handler_deps.js
+++ b/ui/file_manager/file_manager/externs/command_handler_deps.js
@@ -2,34 +2,33 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// clang-format off
-// #import {ActionsController} from '../foreground/js/actions_controller.m.js';
-// #import {FilesAppEntry} from './files_app_entry_interfaces.m.js';
-// #import {Crostini} from './background/crostini.js';
-// #import {MetadataModel} from '../foreground/js/metadata/metadata_model.js';
-// #import {VolumeManager} from './volume_manager.m.js';
-// #import {FileManagerUI} from '../foreground/js/ui/file_manager_ui.js';
-// #import {TaskController} from '../foreground/js/task_controller.m.js';
-// #import {SpinnerController} from '../foreground/js/spinner_controller.m.js';
-// #import {ProvidersModel} from '../foreground/js/providers_model.m.js';
-// #import {ProgressCenter} from './background/progress_center.js';
-// #import {NamingController} from '../foreground/js/naming_controller.m.js';
-// #import {FileSelectionHandler, FileSelection} from '../foreground/js/file_selection.m.js';
-// #import {FileTransferController} from '../foreground/js/file_transfer_controller.m.js';
-// #import {FileOperationManager} from './background/file_operation_manager.js';
-// #import {FileFilter} from '../foreground/js/directory_contents.m.js';
-// #import {DirectoryTreeNamingController} from '../foreground/js/directory_tree_naming_controller.m.js';
-// #import {DirectoryTree} from '../foreground/js/ui/directory_tree.js';
-// #import {DirectoryModel} from '../foreground/js/directory_model.m.js';
-// #import {DialogType} from '../foreground/js/dialog_type.m.js';
-// clang-format on
+import {ActionsController} from '../foreground/js/actions_controller.m.js';
+import {DialogType} from '../foreground/js/dialog_type.m.js';
+import {FileFilter} from '../foreground/js/directory_contents.m.js';
+import {DirectoryModel} from '../foreground/js/directory_model.m.js';
+import {DirectoryTreeNamingController} from '../foreground/js/directory_tree_naming_controller.m.js';
+import {FileSelection, FileSelectionHandler} from '../foreground/js/file_selection.m.js';
+import {FileTransferController} from '../foreground/js/file_transfer_controller.m.js';
+import {MetadataModel} from '../foreground/js/metadata/metadata_model.js';
+import {NamingController} from '../foreground/js/naming_controller.m.js';
+import {ProvidersModel} from '../foreground/js/providers_model.m.js';
+import {SpinnerController} from '../foreground/js/spinner_controller.m.js';
+import {TaskController} from '../foreground/js/task_controller.m.js';
+import {DirectoryTree} from '../foreground/js/ui/directory_tree.js';
+import {FileManagerUI} from '../foreground/js/ui/file_manager_ui.js';
+
+import {Crostini} from './background/crostini.js';
+import {FileOperationManager} from './background/file_operation_manager.js';
+import {ProgressCenter} from './background/progress_center.js';
+import {FilesAppEntry} from './files_app_entry_interfaces.js';
+import {VolumeManager} from './volume_manager.js';
 
 
 /**
  * Interface on which |CommandHandler| depends.
  * @interface
  */
-/* #export */ class CommandHandlerDeps {
+export class CommandHandlerDeps {
   constructor() {
     /** @type {ActionsController} */
     this.actionsController;
diff --git a/ui/file_manager/file_manager/externs/directory_change_event.js b/ui/file_manager/file_manager/externs/directory_change_event.js
index 7283d728..e3d3ce8 100644
--- a/ui/file_manager/file_manager/externs/directory_change_event.js
+++ b/ui/file_manager/file_manager/externs/directory_change_event.js
@@ -8,9 +8,9 @@
  * as JS module, Closure fails to compile as externs.
  */
 
-// #import {FakeEntry} from './files_app_entry_interfaces.m.js';
+import {FakeEntry} from './files_app_entry_interfaces.js';
 
-/* #export */ class DirectoryChangeEvent extends Event {
+export class DirectoryChangeEvent extends Event {
   /** @param {string} eventName */
   constructor(eventName) {
     super(eventName);
diff --git a/ui/file_manager/file_manager/externs/drive_dialog_controller.js b/ui/file_manager/file_manager/externs/drive_dialog_controller.js
index 510c00f..82483ac 100644
--- a/ui/file_manager/file_manager/externs/drive_dialog_controller.js
+++ b/ui/file_manager/file_manager/externs/drive_dialog_controller.js
@@ -7,7 +7,7 @@
  * show dialogs originating from Drive to the user.
  * @interface
  */
-/* #export */ class DriveDialogControllerInterface {
+export class DriveDialogControllerInterface {
   /**
    * @return {boolean} Whether the dialog is open or not
    */
diff --git a/ui/file_manager/file_manager/externs/entries_changed_event.js b/ui/file_manager/file_manager/externs/entries_changed_event.js
index 36475582..c4d093e 100644
--- a/ui/file_manager/file_manager/externs/entries_changed_event.js
+++ b/ui/file_manager/file_manager/externs/entries_changed_event.js
@@ -2,17 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-/**
- * @fileoverview
- * @suppress {externsValidation} this file is used as externs and also
- * as JS module, Closure fails to compile as JS module.
- */
+import {util} from '../common/js/util.m.js';
 
-// clang-format off
-// #import {util} from '../common/js/util.m.js';
-// clang-format on
-
-/* #export */ class EntriesChangedEvent extends Event {
+export class EntriesChangedEvent extends Event {
   /** @param {string} eventName */
   constructor(eventName) {
     super(eventName);
diff --git a/ui/file_manager/file_manager/externs/entry_location.js b/ui/file_manager/file_manager/externs/entry_location.js
index d98b34b..f2412b6 100644
--- a/ui/file_manager/file_manager/externs/entry_location.js
+++ b/ui/file_manager/file_manager/externs/entry_location.js
@@ -2,17 +2,15 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// clang-format off
-// #import * as wrappedVolumeManagerCommon from '../common/js/volume_manager_types.m.js'; const {VolumeManagerCommon} = wrappedVolumeManagerCommon;
-// #import {VolumeInfo} from './volume_info.m.js';
-// clang-format on
+import {VolumeManagerCommon} from '../common/js/volume_manager_types.m.js';
+import {VolumeInfo} from './volume_info.js';
 
 /**
  * Location information which shows where the path points in FileManager's
  * file system.
  * @interface
  */
-/* #export */ class EntryLocation {
+export class EntryLocation {
   constructor() {
     /**
      * Volume information.
diff --git a/ui/file_manager/file_manager/externs/exif_entry.js b/ui/file_manager/file_manager/externs/exif_entry.js
index be54392..c5d9c97 100644
--- a/ui/file_manager/file_manager/externs/exif_entry.js
+++ b/ui/file_manager/file_manager/externs/exif_entry.js
@@ -2,13 +2,11 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// clang-format off
-// #import {Exif} from '../foreground/js/metadata/exif_constants.js';
-// clang-format on
+import {Exif} from '../foreground/js/metadata/exif_constants.js';
 
 /**
  * Type definition of exif entry.
  * @typedef {{id:!Exif.Tag, format:number, componentCount:number,
  *     value:(undefined|*)}}
  */
-/* #export */ let ExifEntry;
+export let ExifEntry;
diff --git a/ui/file_manager/file_manager/externs/files_app_entry_interfaces.js b/ui/file_manager/file_manager/externs/files_app_entry_interfaces.js
index b906b6b..6faa1ca 100644
--- a/ui/file_manager/file_manager/externs/files_app_entry_interfaces.js
+++ b/ui/file_manager/file_manager/externs/files_app_entry_interfaces.js
@@ -6,9 +6,7 @@
  * @fileoverview Interfaces for the Files app Entry Types.
  */
 
-// clang-format off
-// #import * as wrappedVolumeManagerCommon from '../common/js/volume_manager_types.m.js'; const {VolumeManagerCommon} = wrappedVolumeManagerCommon;
-// clang-format on
+import {VolumeManagerCommon} from '../common/js/volume_manager_types.m.js';
 
 /**
  * FilesAppEntry represents a single Entry (file, folder or root) in the Files
@@ -21,7 +19,7 @@
  *
  * @interface
  */
-/* #export */ class FilesAppEntry {
+export class FilesAppEntry {
   constructor() {
     /**
      * @public {boolean} true if this entry represents a Directory-like entry,
@@ -119,7 +117,7 @@
  *
  * @interface
  */
-/* #export */ class FilesAppDirEntry extends FilesAppEntry {
+export class FilesAppDirEntry extends FilesAppEntry {
   constructor() {
     super();
     /**
@@ -147,7 +145,7 @@
  *
  * @interface
  */
-/* #export */ class FakeEntry extends FilesAppDirEntry {
+export class FakeEntry extends FilesAppDirEntry {
   /**
    * @param {string} label Translated text to be displayed to user.
    * @param {!VolumeManagerCommon.RootType} rootType Root type of this entry.
diff --git a/ui/file_manager/file_manager/externs/metadata_worker_window.js b/ui/file_manager/file_manager/externs/metadata_worker_window.js
index 5036d3b..0c710ba5 100644
--- a/ui/file_manager/file_manager/externs/metadata_worker_window.js
+++ b/ui/file_manager/file_manager/externs/metadata_worker_window.js
@@ -5,7 +5,7 @@
 /**
  * @interface
  */
-/* #export */ class MetadataParserLogger {
+export class MetadataParserLogger {
   constructor() {
     /**
      * Verbose logging for the dispatcher.
@@ -43,5 +43,5 @@
  * @param {function(!Entry)} successCallback
  * @param {function(!FileError)=} opt_errorCallback
  */
-/* #export */ const webkitResolveLocalFileSystemURL = function(
+export const webkitResolveLocalFileSystemURL = function(
     url, successCallback, opt_errorCallback) {};
diff --git a/ui/file_manager/file_manager/externs/progress_center_panel.js b/ui/file_manager/file_manager/externs/progress_center_panel.js
index 962e16c..dcef796 100644
--- a/ui/file_manager/file_manager/externs/progress_center_panel.js
+++ b/ui/file_manager/file_manager/externs/progress_center_panel.js
@@ -2,9 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// clang-format off
-// #import {ProgressCenterItem, ProgressItemState} from '../common/js/progress_center_common.m.js';
-// clang-format on
+import {ProgressCenterItem, ProgressItemState} from '../common/js/progress_center_common.m.js';
 
 /**
  * Interface implemented in foreground page that the background page uses to
@@ -12,7 +10,7 @@
  * and dismiss events from the foreground page.
  * @interface
  */
-/* #export */ class ProgressCenterPanelInterface {
+export class ProgressCenterPanelInterface {
   constructor() {
     /**
      * Callback to be called with the ID of the progress item when the cancel
diff --git a/ui/file_manager/file_manager/externs/volume_info.js b/ui/file_manager/file_manager/externs/volume_info.js
index a7c2974..2555bfa 100644
--- a/ui/file_manager/file_manager/externs/volume_info.js
+++ b/ui/file_manager/file_manager/externs/volume_info.js
@@ -2,17 +2,16 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// clang-format off
-// #import * as wrappedVolumeManagerCommon from '../common/js/volume_manager_types.m.js'; const {VolumeManagerCommon} = wrappedVolumeManagerCommon;
-// #import {FilesAppEntry, FakeEntry} from './files_app_entry_interfaces.m.js';
-// clang-format on
+import {VolumeManagerCommon} from '../common/js/volume_manager_types.m.js';
+
+import {FakeEntry, FilesAppEntry} from './files_app_entry_interfaces.js';
 
 /**
  * Represents each volume, such as "drive", "download directory", each "USB
  * flush storage", or "mounted zip archive" etc.
  * @interface
  */
-/* #export */ class VolumeInfo {
+export class VolumeInfo {
   constructor() {
     /** @type {VolumeManagerCommon.VolumeType} */
     this.volumeType;
diff --git a/ui/file_manager/file_manager/externs/volume_info_list.js b/ui/file_manager/file_manager/externs/volume_info_list.js
index 8b8a365..aebe3be 100644
--- a/ui/file_manager/file_manager/externs/volume_info_list.js
+++ b/ui/file_manager/file_manager/externs/volume_info_list.js
@@ -2,13 +2,13 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// #import {VolumeInfo} from './volume_info.m.js';
+import {VolumeInfo} from './volume_info.js';
 
 /**
  * The container of the VolumeInfo for each mounted volume.
  * @interface
  */
-/* #export */ class VolumeInfoList {
+export class VolumeInfoList {
   constructor() {
     /** @const {number} */
     this.length;
diff --git a/ui/file_manager/file_manager/externs/volume_manager.js b/ui/file_manager/file_manager/externs/volume_manager.js
index 56f0a38..a499b702 100644
--- a/ui/file_manager/file_manager/externs/volume_manager.js
+++ b/ui/file_manager/file_manager/externs/volume_manager.js
@@ -2,19 +2,18 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// clang-format off
-// #import {EntryLocation} from './entry_location.m.js';
-// #import {VolumeInfo} from './volume_info.m.js';
-// #import {VolumeInfoList} from './volume_info_list.m.js';
-// #import {FilesAppEntry, FilesAppDirEntry} from './files_app_entry_interfaces.m.js';
-// #import {VolumeManagerCommon} from '../common/js/volume_manager_types.m.js';
-// clang-format on
+import {VolumeManagerCommon} from '../common/js/volume_manager_types.m.js';
+
+import {EntryLocation} from './entry_location.js';
+import {FilesAppDirEntry, FilesAppEntry} from './files_app_entry_interfaces.js';
+import {VolumeInfo} from './volume_info.js';
+import {VolumeInfoList} from './volume_info_list.js';
 
 /**
  * VolumeManager is responsible for tracking list of mounted volumes.
  * @interface
  */
-/* #export */ class VolumeManager {
+export class VolumeManager {
   constructor() {
     /**
      * The list of VolumeInfo instances for each mounted volume.
@@ -138,4 +137,4 @@
  * Event object which is dispached with 'externally-unmounted' event.
  * @typedef {!CustomEvent<!VolumeInfo>}
  */
-/* #export */ let ExternallyUnmountedEvent;
+export let ExternallyUnmountedEvent;
diff --git a/ui/file_manager/file_manager/foreground/elements/BUILD.gn b/ui/file_manager/file_manager/foreground/elements/BUILD.gn
index 8e4a4af..ec0dae8 100644
--- a/ui/file_manager/file_manager/foreground/elements/BUILD.gn
+++ b/ui/file_manager/file_manager/foreground/elements/BUILD.gn
@@ -75,7 +75,7 @@
     "//ui/file_manager/file_manager/common/js:files_app_entry_types.m",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
+    "//ui/file_manager/file_manager/externs:volume_info",
     "//ui/webui/resources/cr_elements/cr_button:cr_button.m",
     "//ui/webui/resources/cr_elements/cr_dialog:cr_dialog.m",
     "//ui/webui/resources/cr_elements/cr_input:cr_input.m",
diff --git a/ui/file_manager/file_manager/foreground/elements/files_format_dialog.js b/ui/file_manager/file_manager/foreground/elements/files_format_dialog.js
index 659308c..69f8b49e 100644
--- a/ui/file_manager/file_manager/foreground/elements/files_format_dialog.js
+++ b/ui/file_manager/file_manager/foreground/elements/files_format_dialog.js
@@ -17,7 +17,7 @@
 import {EntryList, VolumeEntry} from '../../common/js/files_app_entry_types.m.js';
 import {util} from '../../common/js/util.m.js';
 import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
-import {VolumeInfo} from '../../externs/volume_info.m.js';
+import {VolumeInfo} from '../../externs/volume_info.js';
 
 Polymer({
   _template: html`{__html_template__}`,
diff --git a/ui/file_manager/file_manager/foreground/js/BUILD.gn b/ui/file_manager/file_manager/foreground/js/BUILD.gn
index 13d4c7c..5319abe 100644
--- a/ui/file_manager/file_manager/foreground/js/BUILD.gn
+++ b/ui/file_manager/file_manager/foreground/js/BUILD.gn
@@ -118,7 +118,7 @@
     ":folder_shortcuts_data_model.m",
     "metadata:metadata_model",
     "ui:file_manager_ui",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:drive_sync_handler",
     "//ui/webui/resources/js/cr/ui:context_menu_handler.m",
   ]
@@ -146,7 +146,7 @@
     "//ui/file_manager/file_manager/common/js:metrics.m",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:drive_sync_handler",
     "//ui/webui/resources/js:assert.m",
     "//ui/webui/resources/js:cr.m",
@@ -244,7 +244,7 @@
   deps = [
     ":directory_contents.m",
     ":directory_model.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
     "//ui/webui/resources/js/cr:event_target.m",
   ]
 
@@ -280,7 +280,7 @@
   sources = [ "$root_gen_dir/ui/file_manager/file_manager/foreground/js/mock_navigation_list_model.m.js" ]
   deps = [
     ":navigation_list_model.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/webui/resources/js/cr:event_target.m",
   ]
 
@@ -347,7 +347,7 @@
     "ui:file_manager_ui",
     "//ui/file_manager/file_manager/common/js:importer_common.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
   ]
 
   extra_deps = [ ":modulize" ]
@@ -433,7 +433,7 @@
     "//ui/file_manager/file_manager/common/js:metrics.m",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/webui/resources/js:assert.m",
     "//ui/webui/resources/js:util.m",
     "//ui/webui/resources/js/cr/ui:command.m",
@@ -461,7 +461,6 @@
     "//ui/file_manager/file_manager/common/js:metrics",
     "//ui/file_manager/file_manager/common/js:util",
     "//ui/file_manager/file_manager/common/js:volume_manager_types",
-    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/webui/resources/js:cr",
     "//ui/webui/resources/js/cr/ui:array_data_model",
   ]
@@ -477,8 +476,8 @@
     "//ui/file_manager/file_manager/common/js:metrics.m",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/webui/resources/js:assert.m",
     "//ui/webui/resources/js:cr.m",
     "//ui/webui/resources/js/cr:event_target.m",
@@ -492,8 +491,8 @@
     ":directory_contents.m",
     "//chrome/test/data/webui:chai_assert",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:entry_location.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:entry_location",
+    "//ui/file_manager/file_manager/externs:volume_manager",
   ]
 }
 
@@ -522,10 +521,10 @@
     "//ui/file_manager/file_manager/common/js:metrics.m",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:entries_changed_event.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:entries_changed_event",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
+    "//ui/file_manager/file_manager/externs:volume_info",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:file_operation_manager",
     "//ui/webui/resources/js:assert.m",
     "//ui/webui/resources/js:cr.m",
@@ -549,7 +548,7 @@
   deps = [
     "//ui/file_manager/file_manager/common/js:metrics.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
   ]
 
   extra_deps = [ ":modulize" ]
@@ -569,7 +568,7 @@
     ":directory_model.m",
     "ui:directory_tree",
     "//ui/file_manager/file_manager/common/js:util.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
+    "//ui/file_manager/file_manager/externs:volume_info",
     "//ui/webui/resources/js:assert.m",
     "//ui/webui/resources/js/cr/ui:dialogs.m",
   ]
@@ -587,7 +586,7 @@
   deps = [
     "ui:file_manager_ui",
     "ui:files_confirm_dialog",
-    "//ui/file_manager/file_manager/externs:drive_dialog_controller.m",
+    "//ui/file_manager/file_manager/externs:drive_dialog_controller",
     "//ui/webui/resources/js:load_time_data.m",
   ]
 
@@ -665,8 +664,8 @@
     "metadata:metadata_model",
     "//ui/file_manager/file_manager/common/js:file_type.m",
     "//ui/file_manager/file_manager/common/js:util.m",
-    "//ui/file_manager/file_manager/externs:entry_location.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:entry_location",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/webui/resources/js/cr/ui:array_data_model.m",
   ]
 
@@ -785,9 +784,9 @@
     "//ui/file_manager/file_manager/common/js:storage_adapter.m",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:background_window.m",
-    "//ui/file_manager/file_manager/externs:command_handler_deps.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
+    "//ui/file_manager/file_manager/externs:background_window",
+    "//ui/file_manager/file_manager/externs:command_handler_deps",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
     "//ui/file_manager/file_manager/externs/background:crostini",
     "//ui/file_manager/file_manager/externs/background:file_browser_background_full",
     "//ui/file_manager/file_manager/externs/background:file_operation_manager",
@@ -858,10 +857,10 @@
     "//ui/file_manager/file_manager/common/js:trash",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:command_handler_deps.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:command_handler_deps",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
+    "//ui/file_manager/file_manager/externs:volume_info",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/foreground/elements:files_format_dialog",
     "//ui/webui/resources/js:assert.m",
     "//ui/webui/resources/js/cr/ui:command.m",
@@ -907,7 +906,7 @@
     "//ui/file_manager/file_manager/common/js:file_type.m",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:file_operation_manager",
     "//ui/webui/resources/js:assert.m",
     "//ui/webui/resources/js:cr.m",
@@ -954,8 +953,8 @@
     "//ui/file_manager/file_manager/common/js:progress_center_common.m",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_info",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:crostini",
     "//ui/file_manager/file_manager/externs/background:progress_center",
     "//ui/file_manager/file_manager/foreground/elements:files_password_dialog",
@@ -985,8 +984,8 @@
     "//ui/file_manager/file_manager/common/js:progress_center_common.m",
     "//ui/file_manager/file_manager/common/js:test_error_reporting.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:entry_location.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:entry_location",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:progress_center",
     "//ui/file_manager/file_manager/foreground/elements:files_password_dialog",
   ]
@@ -1021,10 +1020,10 @@
     "//ui/file_manager/file_manager/common/js:progress_center_common.m",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:entry_location.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:entry_location",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
+    "//ui/file_manager/file_manager/externs:volume_info",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:file_operation_manager",
     "//ui/file_manager/file_manager/externs/background:progress_center",
     "//ui/webui/resources/js:assert.m",
@@ -1057,7 +1056,7 @@
     "//ui/file_manager/file_manager/common/js:mock_chrome.m",
     "//ui/file_manager/file_manager/common/js:mock_entry.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:file_operation_manager",
     "//ui/file_manager/file_manager/externs/background:import_history",
     "//ui/file_manager/file_manager/externs/background:progress_center",
@@ -1080,7 +1079,7 @@
   deps = [
     ":directory_model.m",
     "//ui/file_manager/file_manager/common/js:util.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
   ]
 
   extra_deps = [ ":modulize" ]
@@ -1094,7 +1093,7 @@
     "//ui/file_manager/file_manager/common/js:files_app_entry_types.m",
     "//ui/file_manager/file_manager/common/js:mock_chrome",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
     "//ui/webui/resources/js:load_time_data.m",
     "//ui/webui/resources/js/cr:event_target.m",
   ]
@@ -1114,7 +1113,7 @@
   deps = [
     "//ui/file_manager/file_manager/common/js:async_util.m",
     "//ui/file_manager/file_manager/common/js:util.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
     "//ui/webui/resources/js:assert.m",
     "//ui/webui/resources/js/cr:event_target.m",
   ]
@@ -1165,7 +1164,7 @@
     "ui:providers_menu",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:directory_change_event.m",
+    "//ui/file_manager/file_manager/externs:directory_change_event",
   ]
 
   extra_deps = [ ":modulize" ]
@@ -1218,10 +1217,10 @@
     "//ui/file_manager/file_manager/common/js:metrics.m",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:command_handler_deps.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:command_handler_deps",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
+    "//ui/file_manager/file_manager/externs:volume_info",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:media_import_handler",
     "//ui/file_manager/file_manager/externs/background:media_scanner",
     "//ui/webui/resources/js:assert.m",
@@ -1242,8 +1241,8 @@
     "//ui/file_manager/file_manager/common/js:mock_entry.m",
     "//ui/file_manager/file_manager/common/js:test_error_reporting.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_info",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:media_import_handler",
     "//ui/file_manager/file_manager/externs/background:media_scanner",
     "//ui/webui/resources/js:assert.m",
@@ -1300,7 +1299,7 @@
     "metadata:thumbnail_model",
     "//ui/file_manager/file_manager/common/js:lru_cache.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/webui/resources/js:assert.m",
     "//ui/webui/resources/js/cr:event_target.m",
   ]
@@ -1320,7 +1319,7 @@
     "//ui/file_manager/file_manager/common/js:mock_entry.m",
     "//ui/file_manager/file_manager/common/js:test_error_reporting.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/webui/resources/js:assert.m",
     "//ui/webui/resources/js/cr:event_target.m",
   ]
@@ -1372,8 +1371,8 @@
     "//ui/file_manager/file_manager/common/js:metrics.m",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:directory_change_event.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:directory_change_event",
+    "//ui/file_manager/file_manager/externs:volume_manager",
   ]
 
   extra_deps = [ ":modulize" ]
@@ -1396,7 +1395,7 @@
     "ui:file_metadata_formatter",
     "//ui/file_manager/file_manager/common/js:file_type.m",
     "//ui/file_manager/file_manager/common/js:util.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/foreground/elements:files_metadata_box",
     "//ui/file_manager/file_manager/foreground/elements:files_quick_view",
     "//ui/webui/resources/js:assert.m",
@@ -1477,9 +1476,9 @@
     "//ui/file_manager/file_manager/common/js:trash",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
+    "//ui/file_manager/file_manager/externs:volume_info",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/webui/resources/js:load_time_data.m",
     "//ui/webui/resources/js/cr:event_target.m",
   ]
@@ -1504,7 +1503,7 @@
     "//ui/file_manager/file_manager/common/js:test_error_reporting.m",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
   ]
 }
 
@@ -1517,7 +1516,7 @@
   deps = [
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
   ]
 
   extra_deps = [ ":modulize" ]
@@ -1531,7 +1530,7 @@
   sources = [ "$root_gen_dir/ui/file_manager/file_manager/foreground/js/providers_model.m.js" ]
   deps = [
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/webui/resources/js:assert.m",
   ]
 
@@ -1548,7 +1547,7 @@
     "//ui/file_manager/file_manager/common/js:mock_entry.m",
     "//ui/file_manager/file_manager/common/js:test_error_reporting.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
   ]
 }
 
@@ -1586,8 +1585,8 @@
     "//ui/file_manager/file_manager/common/js:file_type.m",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:command_handler_deps.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:command_handler_deps",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/foreground/elements:files_quick_view",
     "//ui/file_manager/image_loader:image_loader_client",
     "//ui/file_manager/image_loader:load_image_request",
@@ -1630,7 +1629,7 @@
     "//ui/file_manager/file_manager/common/js:file_type.m",
     "//ui/file_manager/file_manager/common/js:metrics.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/webui/resources/js:assert.m",
   ]
 
@@ -1676,8 +1675,8 @@
     "ui:search_box",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:entry_location.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:entry_location",
+    "//ui/file_manager/file_manager/externs:volume_manager",
   ]
 
   extra_deps = [ ":modulize" ]
@@ -1764,7 +1763,7 @@
     "metadata:metadata_model",
     "ui:file_manager_ui",
     "//ui/file_manager/file_manager/common/js:util.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:crostini",
     "//ui/file_manager/file_manager/externs/background:progress_center",
     "//ui/webui/resources/js:assert.m",
@@ -1794,7 +1793,7 @@
     "//ui/file_manager/file_manager/common/js:test_error_reporting.m",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:progress_center",
     "//ui/webui/resources/js:assert.m",
     "//ui/webui/resources/js/cr:ui.m",
@@ -1869,7 +1868,7 @@
     "ui:location_line",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/webui/resources/js:assert.m",
     "//ui/webui/resources/js:util.m",
     "//ui/webui/resources/js/cr/ui:command.m",
diff --git a/ui/file_manager/file_manager/foreground/js/actions_controller.js b/ui/file_manager/file_manager/foreground/js/actions_controller.js
index a54fc4b..b12d35d 100644
--- a/ui/file_manager/file_manager/foreground/js/actions_controller.js
+++ b/ui/file_manager/file_manager/foreground/js/actions_controller.js
@@ -8,7 +8,7 @@
 // #import {FolderShortcutsDataModel} from './folder_shortcuts_data_model.m.js';
 // #import {DirectoryModel} from './directory_model.m.js';
 // #import {MetadataModel} from './metadata/metadata_model.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {Action, ActionsModel} from './actions_model.m.js';
 // #import {contextMenuHandler} from 'chrome://resources/js/cr/ui/context_menu_handler.m.js';
 // clang-format on
diff --git a/ui/file_manager/file_manager/foreground/js/actions_model.js b/ui/file_manager/file_manager/foreground/js/actions_model.js
index fcbf8da..dfb1775c 100644
--- a/ui/file_manager/file_manager/foreground/js/actions_model.js
+++ b/ui/file_manager/file_manager/foreground/js/actions_model.js
@@ -6,7 +6,7 @@
 // #import {ActionModelUI} from './ui/action_model_ui.js';
 // #import {FolderShortcutsDataModel} from './folder_shortcuts_data_model.m.js';
 // #import {DriveSyncHandler} from '../../externs/background/drive_sync_handler.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {MetadataModel} from './metadata/metadata_model.js';
 // #import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
 // #import {util, str, strf} from '../../common/js/util.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/column_visibility_controller.js b/ui/file_manager/file_manager/foreground/js/column_visibility_controller.js
index ee40a76..47b39f8 100644
--- a/ui/file_manager/file_manager/foreground/js/column_visibility_controller.js
+++ b/ui/file_manager/file_manager/foreground/js/column_visibility_controller.js
@@ -3,7 +3,7 @@
 // found in the LICENSE file.
 
 // clang-format off
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {DirectoryModel} from './directory_model.m.js';
 // #import {FileManagerUI} from './ui/file_manager_ui.js';
 // #import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/dialog_action_controller.js b/ui/file_manager/file_manager/foreground/js/dialog_action_controller.js
index a8257fd..18323256 100644
--- a/ui/file_manager/file_manager/foreground/js/dialog_action_controller.js
+++ b/ui/file_manager/file_manager/foreground/js/dialog_action_controller.js
@@ -6,7 +6,7 @@
 // #import {LaunchParam} from './launch_param.m.js';
 // #import {NamingController} from './naming_controller.m.js';
 // #import {FileFilter} from './directory_contents.m.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {MetadataModel} from './metadata/metadata_model.js';
 // #import {DirectoryModel} from './directory_model.m.js';
 // #import {DialogFooter} from './ui/dialog_footer.js';
diff --git a/ui/file_manager/file_manager/foreground/js/directory_contents.js b/ui/file_manager/file_manager/foreground/js/directory_contents.js
index 089b63ec..56949a5d 100644
--- a/ui/file_manager/file_manager/foreground/js/directory_contents.js
+++ b/ui/file_manager/file_manager/foreground/js/directory_contents.js
@@ -4,8 +4,8 @@
 
 // clang-format off
 // #import {MetadataModel} from './metadata/metadata_model.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
-// #import {FilesAppDirEntry, FakeEntry} from '../../externs/files_app_entry_interfaces.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
+// #import {FilesAppDirEntry, FakeEntry} from '../../externs/files_app_entry_interfaces.js';
 // #import {FileListModel} from './file_list_model.m.js';
 // #import {AsyncUtil} from '../../common/js/async_util.m.js';
 // #import {constants} from './constants.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/directory_contents_unittest.m.js b/ui/file_manager/file_manager/foreground/js/directory_contents_unittest.m.js
index 647caffd..6c035f4 100644
--- a/ui/file_manager/file_manager/foreground/js/directory_contents_unittest.m.js
+++ b/ui/file_manager/file_manager/foreground/js/directory_contents_unittest.m.js
@@ -5,8 +5,8 @@
 import {assertEquals, assertFalse} from 'chrome://test/chai_assert.js';
 import {installMockChrome} from '../../common/js/mock_chrome.m.js';
 import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
-import {EntryLocation} from '../../externs/entry_location.m.js';
-import {VolumeManager} from '../../externs/volume_manager.m.js';
+import {EntryLocation} from '../../externs/entry_location.js';
+import {VolumeManager} from '../../externs/volume_manager.js';
 import {FileFilter} from './directory_contents.m.js';
 
 /**
diff --git a/ui/file_manager/file_manager/foreground/js/directory_model.js b/ui/file_manager/file_manager/foreground/js/directory_model.js
index 894b6e8..14059e6 100644
--- a/ui/file_manager/file_manager/foreground/js/directory_model.js
+++ b/ui/file_manager/file_manager/foreground/js/directory_model.js
@@ -3,13 +3,13 @@
 // found in the LICENSE file.
 
 // clang-format off
-// #import {EntriesChangedEvent} from '../../externs/entries_changed_event.m.js';
+// #import {EntriesChangedEvent} from '../../externs/entries_changed_event.js';
 // #import {ListSingleSelectionModel} from 'chrome://resources/js/cr/ui/list_single_selection_model.m.js';
 // #import {ListSelectionModel} from 'chrome://resources/js/cr/ui/list_selection_model.m.js';
-// #import {VolumeInfo} from '../../externs/volume_info.m.js';
-// #import {FilesAppDirEntry, FakeEntry, FilesAppEntry} from '../../externs/files_app_entry_interfaces.m.js';
+// #import {VolumeInfo} from '../../externs/volume_info.js';
+// #import {FilesAppDirEntry, FakeEntry, FilesAppEntry} from '../../externs/files_app_entry_interfaces.js';
 // #import {FileOperationManager} from '../../externs/background/file_operation_manager.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {MetadataModel} from './metadata/metadata_model.js';
 // #import {FileListSingleSelectionModel, FileListSelectionModel} from './ui/file_list_selection_model.js';
 // #import {FileWatcher} from './file_watcher.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/directory_tree_naming_controller.js b/ui/file_manager/file_manager/foreground/js/directory_tree_naming_controller.js
index a6cdbcc..72c3924a 100644
--- a/ui/file_manager/file_manager/foreground/js/directory_tree_naming_controller.js
+++ b/ui/file_manager/file_manager/foreground/js/directory_tree_naming_controller.js
@@ -3,7 +3,7 @@
 // found in the LICENSE file.
 
 // #import {DirectoryTree, DirectoryItem} from './ui/directory_tree.js';
-// #import {VolumeInfo} from '../../externs/volume_info.m.js';
+// #import {VolumeInfo} from '../../externs/volume_info.js';
 // #import {AlertDialog} from 'chrome://resources/js/cr/ui/dialogs.m.js';
 // #import {DirectoryModel} from './directory_model.m.js';
 // #import {util} from '../../common/js/util.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/drive_dialog_controller.js b/ui/file_manager/file_manager/foreground/js/drive_dialog_controller.js
index 096d6b7..49d2ad8 100644
--- a/ui/file_manager/file_manager/foreground/js/drive_dialog_controller.js
+++ b/ui/file_manager/file_manager/foreground/js/drive_dialog_controller.js
@@ -3,7 +3,7 @@
 // found in the LICENSE file.
 
 // clang-format off
-// #import {DriveDialogControllerInterface} from '../../externs/drive_dialog_controller.m.js';
+// #import {DriveDialogControllerInterface} from '../../externs/drive_dialog_controller.js';
 // #import {FileManagerUI} from './ui/file_manager_ui.js';
 // #import {FilesConfirmDialog} from './ui/files_confirm_dialog.js';
 // #import {loadTimeData} from 'chrome://resources/js/load_time_data.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/file_list_model.js b/ui/file_manager/file_manager/foreground/js/file_list_model.js
index 587e5a4..c6ba4c7 100644
--- a/ui/file_manager/file_manager/foreground/js/file_list_model.js
+++ b/ui/file_manager/file_manager/foreground/js/file_list_model.js
@@ -3,8 +3,8 @@
 // found in the LICENSE file.
 
 // clang-format off
-// #import {EntryLocation} from '../../externs/entry_location.m.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {EntryLocation} from '../../externs/entry_location.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {MetadataModel} from './metadata/metadata_model.js';
 // #import {FileType} from '../../common/js/file_type.m.js';
 // #import {strf, str, util} from '../../common/js/util.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/file_manager.js b/ui/file_manager/file_manager/foreground/js/file_manager.js
index 58d05f1..5e086a6 100644
--- a/ui/file_manager/file_manager/foreground/js/file_manager.js
+++ b/ui/file_manager/file_manager/foreground/js/file_manager.js
@@ -9,15 +9,15 @@
 // #import {FileListSelectionModel} from './ui/file_list_selection_model.js';
 // #import {A11yAnnounce} from './ui/a11y_announce.js';
 // #import {ProgressCenter} from '../../externs/background/progress_center.js';
-// #import {FakeEntry, FilesAppDirEntry} from '../../externs/files_app_entry_interfaces.m.js';
+// #import {FakeEntry, FilesAppDirEntry} from '../../externs/files_app_entry_interfaces.js';
 // #import {FileBrowserBackgroundFull} from '../../externs/background/file_browser_background_full.js';
-// #import {BackgroundWindow} from '../../externs/background_window.m.js';
+// #import {BackgroundWindow} from '../../externs/background_window.js';
 // #import {FileOperationManager} from '../../externs/background/file_operation_manager.js';
 // #import {mediaImportInterfaces} from '../../externs/background/media_import_handler.js';
 // #import {mediaScannerInterfaces} from '../../externs/background/media_scanner.js';
 // #import {Crostini} from '../../externs/background/crostini.js';
 // #import {importerHistoryInterfaces} from '../../externs/background/import_history.js';
-// #import {CommandHandlerDeps} from '../../externs/command_handler_deps.m.js';
+// #import {CommandHandlerDeps} from '../../externs/command_handler_deps.js';
 // #import {ProgressItemState} from '../../common/js/progress_center_common.m.js';
 // #import {xfm} from '../../common/js/xfm.m.js';
 // #import {crossoverSearchUtils} from './crossover_search_utils.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/file_manager_commands.js b/ui/file_manager/file_manager/foreground/js/file_manager_commands.js
index 90064593..37ae5f8 100644
--- a/ui/file_manager/file_manager/foreground/js/file_manager_commands.js
+++ b/ui/file_manager/file_manager/foreground/js/file_manager_commands.js
@@ -11,12 +11,12 @@
 // #import {TrashEntry} from '../../common/js/trash.js';
 // #import {FileOperationProgressEvent} from '../../common/js/file_operation_common.m.js';
 // #import {FilesConfirmDialog} from './ui/files_confirm_dialog.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {FileSelection, FileSelectionHandler} from './file_selection.m.js';
-// #import {VolumeInfo} from '../../externs/volume_info.m.js';
+// #import {VolumeInfo} from '../../externs/volume_info.js';
 // #import {DirectoryModel} from './directory_model.m.js';
-// #import {FakeEntry, FilesAppEntry, FilesAppDirEntry} from '../../externs/files_app_entry_interfaces.m.js';
-// #import {CommandHandlerDeps} from '../../externs/command_handler_deps.m.js';
+// #import {FakeEntry, FilesAppEntry, FilesAppDirEntry} from '../../externs/files_app_entry_interfaces.js';
+// #import {CommandHandlerDeps} from '../../externs/command_handler_deps.js';
 // #import {FileType} from '../../common/js/file_type.m.js';
 // #import {constants} from './constants.m.js';
 // #import {ProgressCenterItem, ProgressItemState} from '../../common/js/progress_center_common.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/file_selection.js b/ui/file_manager/file_manager/foreground/js/file_selection.js
index 421d3cd..eaa323d 100644
--- a/ui/file_manager/file_manager/foreground/js/file_selection.js
+++ b/ui/file_manager/file_manager/foreground/js/file_selection.js
@@ -7,7 +7,7 @@
 // #import {ListContainer} from './ui/list_container.js';
 // #import {FileOperationManager} from '../../externs/background/file_operation_manager.js';
 // #import {DirectoryModel} from './directory_model.m.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {AllowedPaths} from '../../common/js/volume_manager_types.m.js';
 // #import {util} from '../../common/js/util.m.js';
 // #import {constants} from './constants.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/file_tasks.js b/ui/file_manager/file_manager/foreground/js/file_tasks.js
index b96734a..91ea8d4 100644
--- a/ui/file_manager/file_manager/foreground/js/file_tasks.js
+++ b/ui/file_manager/file_manager/foreground/js/file_tasks.js
@@ -5,7 +5,7 @@
 // clang-format off
 // #import {Menu} from 'chrome://resources/js/cr/ui/menu.m.js';
 // #import {MultiMenuButton} from './ui/multi_menu_button.js';
-// #import {VolumeInfo} from '../../externs/volume_info.m.js';
+// #import {VolumeInfo} from '../../externs/volume_info.js';
 // #import {ProgressCenter} from '../../externs/background/progress_center.js';
 // #import {Crostini} from '../../externs/background/crostini.js';
 // #import {NamingController} from './naming_controller.m.js';
@@ -13,7 +13,7 @@
 // #import {FileManagerUI} from './ui/file_manager_ui.js';
 // #import {DirectoryModel} from './directory_model.m.js';
 // #import {MetadataModel} from './metadata/metadata_model.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {FilesMenuItem} from './ui/files_menu.js';
 // #import {decorate} from 'chrome://resources/js/cr/ui.m.js';
 // #import {FilesPasswordDialog} from '../elements/files_password_dialog.js';
diff --git a/ui/file_manager/file_manager/foreground/js/file_tasks_unittest.m.js b/ui/file_manager/file_manager/foreground/js/file_tasks_unittest.m.js
index fb4e311..7699028 100644
--- a/ui/file_manager/file_manager/foreground/js/file_tasks_unittest.m.js
+++ b/ui/file_manager/file_manager/foreground/js/file_tasks_unittest.m.js
@@ -13,8 +13,8 @@
 import {reportPromise} from '../../common/js/test_error_reporting.m.js';
 import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
 import {ProgressCenter} from '../../externs/background/progress_center.js';
-import {EntryLocation} from '../../externs/entry_location.m.js';
-import {VolumeManager} from '../../externs/volume_manager.m.js';
+import {EntryLocation} from '../../externs/entry_location.js';
+import {VolumeManager} from '../../externs/volume_manager.js';
 import {FilesPasswordDialog} from '../elements/files_password_dialog.js';
 
 import {DirectoryModel} from './directory_model.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/file_transfer_controller.js b/ui/file_manager/file_manager/foreground/js/file_transfer_controller.js
index d9c95c1..cc6c9d6 100644
--- a/ui/file_manager/file_manager/foreground/js/file_transfer_controller.js
+++ b/ui/file_manager/file_manager/foreground/js/file_transfer_controller.js
@@ -3,12 +3,12 @@
 // found in the LICENSE file.
 
 // clang-format off
-// #import {EntryLocation} from '../../externs/entry_location.m.js';
-// #import {VolumeInfo} from '../../externs/volume_info.m.js';
+// #import {EntryLocation} from '../../externs/entry_location.js';
+// #import {VolumeInfo} from '../../externs/volume_info.js';
 // #import {List} from 'chrome://resources/js/cr/ui/list.m.js';
-// #import {FilesAppDirEntry, FakeEntry, FilesAppEntry} from '../../externs/files_app_entry_interfaces.m.js';
+// #import {FilesAppDirEntry, FakeEntry, FilesAppEntry} from '../../externs/files_app_entry_interfaces.js';
 // #import {Command} from 'chrome://resources/js/cr/ui/command.m.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {DirectoryModel} from './directory_model.m.js';
 // #import {MetadataModel} from './metadata/metadata_model.js';
 // #import {FileOperationManager} from '../../externs/background/file_operation_manager.js';
diff --git a/ui/file_manager/file_manager/foreground/js/file_transfer_controller_unittest.m.js b/ui/file_manager/file_manager/foreground/js/file_transfer_controller_unittest.m.js
index b787d71..c7e1ca1 100644
--- a/ui/file_manager/file_manager/foreground/js/file_transfer_controller_unittest.m.js
+++ b/ui/file_manager/file_manager/foreground/js/file_transfer_controller_unittest.m.js
@@ -15,7 +15,7 @@
 import {FileOperationManager} from '../../externs/background/file_operation_manager.js';
 import {importerHistoryInterfaces} from '../../externs/background/import_history.js';
 import {ProgressCenter} from '../../externs/background/progress_center.js';
-import {VolumeManager} from '../../externs/volume_manager.m.js';
+import {VolumeManager} from '../../externs/volume_manager.js';
 
 import {DialogType} from './dialog_type.m.js';
 import {FakeFileSelectionHandler} from './fake_file_selection_handler.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/file_type_filters_controller.js b/ui/file_manager/file_manager/foreground/js/file_type_filters_controller.js
index 6c02cc4..2779a44 100644
--- a/ui/file_manager/file_manager/foreground/js/file_type_filters_controller.js
+++ b/ui/file_manager/file_manager/foreground/js/file_type_filters_controller.js
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// #import {FakeEntry} from '../../externs/files_app_entry_interfaces.m.js';
+// #import {FakeEntry} from '../../externs/files_app_entry_interfaces.js';
 // #import {DirectoryModel} from './directory_model.m.js';
 // #import {str, util} from '../../common/js/util.m.js';
 
diff --git a/ui/file_manager/file_manager/foreground/js/file_type_filters_controller_unittest.m.js b/ui/file_manager/file_manager/foreground/js/file_type_filters_controller_unittest.m.js
index eeeb307..b01cc9a 100644
--- a/ui/file_manager/file_manager/foreground/js/file_type_filters_controller_unittest.m.js
+++ b/ui/file_manager/file_manager/foreground/js/file_type_filters_controller_unittest.m.js
@@ -9,7 +9,7 @@
 import {EntryList, FakeEntryImpl} from '../../common/js/files_app_entry_types.m.js';
 import {installMockChrome} from '../../common/js/mock_chrome.m.js';
 import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
-import {FakeEntry} from '../../externs/files_app_entry_interfaces.m.js';
+import {FakeEntry} from '../../externs/files_app_entry_interfaces.js';
 
 import {DirectoryModel} from './directory_model.m.js';
 import {FileTypeFiltersController} from './file_type_filters_controller.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/file_watcher.js b/ui/file_manager/file_manager/foreground/js/file_watcher.js
index d92993b..4225ad0 100644
--- a/ui/file_manager/file_manager/foreground/js/file_watcher.js
+++ b/ui/file_manager/file_manager/foreground/js/file_watcher.js
@@ -3,7 +3,7 @@
 // found in the LICENSE file.
 
 // clang-format off
-// #import {FilesAppEntry} from '../../externs/files_app_entry_interfaces.m.js';
+// #import {FilesAppEntry} from '../../externs/files_app_entry_interfaces.js';
 // #import {assert} from 'chrome://resources/js/assert.m.js';
 // #import {util} from '../../common/js/util.m.js';
 // #import {AsyncUtil} from '../../common/js/async_util.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/gear_menu_controller.js b/ui/file_manager/file_manager/foreground/js/gear_menu_controller.js
index c1dacbf..189375f 100644
--- a/ui/file_manager/file_manager/foreground/js/gear_menu_controller.js
+++ b/ui/file_manager/file_manager/foreground/js/gear_menu_controller.js
@@ -10,7 +10,7 @@
 // #import {GearMenu} from './ui/gear_menu.js';
 // #import {MultiMenuButton} from './ui/multi_menu_button.js';
 // #import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
-// #import {DirectoryChangeEvent} from '../../externs/directory_change_event.m.js';
+// #import {DirectoryChangeEvent} from '../../externs/directory_change_event.js';
 // #import {str, util} from '../../common/js/util.m.js';
 // clang-format on
 
diff --git a/ui/file_manager/file_manager/foreground/js/import_controller.js b/ui/file_manager/file_manager/foreground/js/import_controller.js
index 8d0894f..ab0cfda4 100644
--- a/ui/file_manager/file_manager/foreground/js/import_controller.js
+++ b/ui/file_manager/file_manager/foreground/js/import_controller.js
@@ -9,10 +9,10 @@
 
 // clang-format off
 // #import {importer} from '../../common/js/importer_common.m.js';
-// #import {CommandHandlerDeps} from '../../externs/command_handler_deps.m.js';
-// #import {VolumeInfo} from '../../externs/volume_info.m.js';
-// #import {FilesAppEntry} from '../../externs/files_app_entry_interfaces.m.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {CommandHandlerDeps} from '../../externs/command_handler_deps.js';
+// #import {VolumeInfo} from '../../externs/volume_info.js';
+// #import {FilesAppEntry} from '../../externs/files_app_entry_interfaces.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {mediaImportInterfaces} from '../../externs/background/media_import_handler.js';
 // #import {mediaScannerInterfaces} from '../../externs/background/media_scanner.js';
 // #import {FileSelectionHandler} from './file_selection.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/import_controller_unittest.m.js b/ui/file_manager/file_manager/foreground/js/import_controller_unittest.m.js
index 0394a90..7a8eb6c 100644
--- a/ui/file_manager/file_manager/foreground/js/import_controller_unittest.m.js
+++ b/ui/file_manager/file_manager/foreground/js/import_controller_unittest.m.js
@@ -13,8 +13,8 @@
 import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
 import {mediaImportInterfaces} from '../../externs/background/media_import_handler.js';
 import {mediaScannerInterfaces} from '../../externs/background/media_scanner.js';
-import {VolumeInfo} from '../../externs/volume_info.m.js';
-import {VolumeManager} from '../../externs/volume_manager.m.js';
+import {VolumeInfo} from '../../externs/volume_info.js';
+import {VolumeManager} from '../../externs/volume_manager.js';
 
 import {importer} from './import_controller.m.js';
 
diff --git a/ui/file_manager/file_manager/foreground/js/list_thumbnail_loader.js b/ui/file_manager/file_manager/foreground/js/list_thumbnail_loader.js
index 894b65e..0636a4ad 100644
--- a/ui/file_manager/file_manager/foreground/js/list_thumbnail_loader.js
+++ b/ui/file_manager/file_manager/foreground/js/list_thumbnail_loader.js
@@ -4,7 +4,7 @@
 
 // clang-format off
 // #import {FileListModel} from './file_list_model.m.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {ThumbnailModel} from './metadata/thumbnail_model.js';
 // #import {DirectoryModel} from './directory_model.m.js';
 // #import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/list_thumbnail_loader_unittest.m.js b/ui/file_manager/file_manager/foreground/js/list_thumbnail_loader_unittest.m.js
index 60156e4..da69945 100644
--- a/ui/file_manager/file_manager/foreground/js/list_thumbnail_loader_unittest.m.js
+++ b/ui/file_manager/file_manager/foreground/js/list_thumbnail_loader_unittest.m.js
@@ -9,7 +9,7 @@
 import {MockDirectoryEntry, MockEntry, MockFileSystem} from '../../common/js/mock_entry.m.js';
 import {reportPromise, waitUntil} from '../../common/js/test_error_reporting.m.js';
 import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
-import {VolumeManager} from '../../externs/volume_manager.m.js';
+import {VolumeManager} from '../../externs/volume_manager.js';
 
 import {DirectoryModel} from './directory_model.m.js';
 import {FileListModel} from './file_list_model.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/main_window_component.js b/ui/file_manager/file_manager/foreground/js/main_window_component.js
index 15d011664d..4747541 100644
--- a/ui/file_manager/file_manager/foreground/js/main_window_component.js
+++ b/ui/file_manager/file_manager/foreground/js/main_window_component.js
@@ -8,7 +8,7 @@
 // #import {FileSelectionHandler} from './file_selection.m.js';
 // #import {FileFilter} from './directory_contents.m.js';
 // #import {DirectoryModel} from './directory_model.m.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {FileManagerUI} from './ui/file_manager_ui.js';
 // #import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
 // #import {str, util} from '../../common/js/util.m.js';
@@ -17,7 +17,7 @@
 // #import {FileTapHandler} from './ui/file_tap_handler.js';
 // #import {ListContainer} from './ui/list_container.js';
 // #import {AppStateController} from './app_state_controller.m.js';
-// #import {DirectoryChangeEvent} from '../../externs/directory_change_event.m.js';
+// #import {DirectoryChangeEvent} from '../../externs/directory_change_event.js';
 // clang-format on
 
 /**
diff --git a/ui/file_manager/file_manager/foreground/js/metadata/BUILD.gn b/ui/file_manager/file_manager/foreground/js/metadata/BUILD.gn
index ad39eeb..9a9e150b 100644
--- a/ui/file_manager/file_manager/foreground/js/metadata/BUILD.gn
+++ b/ui/file_manager/file_manager/foreground/js/metadata/BUILD.gn
@@ -114,8 +114,8 @@
     ":byte_reader",
     ":exif_constants",
     ":metadata_parser",
-    "//ui/file_manager/file_manager/externs:exif_entry.m",
-    "//ui/file_manager/file_manager/externs:metadata_worker_window.m",
+    "//ui/file_manager/file_manager/externs:exif_entry",
+    "//ui/file_manager/file_manager/externs:metadata_worker_window",
   ]
 }
 
@@ -125,8 +125,8 @@
     ":exif_constants",
     ":exif_parser",
     "//chrome/test/data/webui:chai_assert",
-    "//ui/file_manager/file_manager/externs:exif_entry.m",
-    "//ui/file_manager/file_manager/externs:metadata_worker_window.m",
+    "//ui/file_manager/file_manager/externs:exif_entry",
+    "//ui/file_manager/file_manager/externs:metadata_worker_window",
   ]
 }
 
@@ -180,7 +180,7 @@
     ":function_parallel",
     ":function_sequence",
     ":metadata_parser",
-    "//ui/file_manager/file_manager/externs:metadata_worker_window.m",
+    "//ui/file_manager/file_manager/externs:metadata_worker_window",
   ]
 }
 
@@ -198,7 +198,7 @@
   deps = [
     ":byte_reader",
     ":metadata_parser",
-    "//ui/file_manager/file_manager/externs:metadata_worker_window.m",
+    "//ui/file_manager/file_manager/externs:metadata_worker_window",
   ]
 }
 
@@ -241,7 +241,7 @@
     ":image_parsers",
     ":metadata_parser",
     ":mpeg_parser",
-    "//ui/file_manager/file_manager/externs:metadata_worker_window.m",
+    "//ui/file_manager/file_manager/externs:metadata_worker_window",
   ]
   externs_list = [ "//ui/file_manager/file_manager/externs/platform.js" ]
 }
@@ -259,7 +259,7 @@
     ":metadata_provider",
     ":multi_metadata_provider",
     "//ui/file_manager/file_manager/common/js:util.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
   ]
 }
 
@@ -275,7 +275,7 @@
 js_library("metadata_parser") {
   deps = [
     ":byte_reader",
-    "//ui/file_manager/file_manager/externs:metadata_worker_window.m",
+    "//ui/file_manager/file_manager/externs:metadata_worker_window",
   ]
 }
 
@@ -298,7 +298,7 @@
   deps = [
     ":byte_reader",
     ":metadata_parser",
-    "//ui/file_manager/file_manager/externs:metadata_worker_window.m",
+    "//ui/file_manager/file_manager/externs:metadata_worker_window",
   ]
 }
 
@@ -311,7 +311,7 @@
     ":metadata_provider",
     ":metadata_request",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/webui/resources/js:assert.m",
   ]
 }
@@ -326,7 +326,7 @@
     "//chrome/test/data/webui:chai_assert",
     "//ui/file_manager/file_manager/common/js:test_error_reporting.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
   ]
 }
 
diff --git a/ui/file_manager/file_manager/foreground/js/metadata/exif_parser.js b/ui/file_manager/file_manager/foreground/js/metadata/exif_parser.js
index 3fae95e..88ffabe 100644
--- a/ui/file_manager/file_manager/foreground/js/metadata/exif_parser.js
+++ b/ui/file_manager/file_manager/foreground/js/metadata/exif_parser.js
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import {ExifEntry} from '../../../externs/exif_entry.m.js';
-import {MetadataParserLogger} from '../../../externs/metadata_worker_window.m.js';
+import {ExifEntry} from '../../../externs/exif_entry.js';
+import {MetadataParserLogger} from '../../../externs/metadata_worker_window.js';
 
 import {ByteReader} from './byte_reader.js';
 import {Exif} from './exif_constants.js';
diff --git a/ui/file_manager/file_manager/foreground/js/metadata/exif_parser_unittest.m.js b/ui/file_manager/file_manager/foreground/js/metadata/exif_parser_unittest.m.js
index 40c1340..1ffe643 100644
--- a/ui/file_manager/file_manager/foreground/js/metadata/exif_parser_unittest.m.js
+++ b/ui/file_manager/file_manager/foreground/js/metadata/exif_parser_unittest.m.js
@@ -4,8 +4,8 @@
 
 import {assertEquals, assertTrue} from 'chrome://test/chai_assert.js';
 
-import {ExifEntry} from '../../../externs/exif_entry.m.js';
-import {MetadataParserLogger} from '../../../externs/metadata_worker_window.m.js';
+import {ExifEntry} from '../../../externs/exif_entry.js';
+import {MetadataParserLogger} from '../../../externs/metadata_worker_window.js';
 
 import {ByteReader} from './byte_reader.js';
 import {Exif} from './exif_constants.js';
diff --git a/ui/file_manager/file_manager/foreground/js/metadata/id3_parser.js b/ui/file_manager/file_manager/foreground/js/metadata/id3_parser.js
index 316d5ce7..6197da8 100644
--- a/ui/file_manager/file_manager/foreground/js/metadata/id3_parser.js
+++ b/ui/file_manager/file_manager/foreground/js/metadata/id3_parser.js
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import {MetadataParserLogger} from '../../../externs/metadata_worker_window.m.js';
+import {MetadataParserLogger} from '../../../externs/metadata_worker_window.js';
 
 import {ByteReader} from './byte_reader.js';
 import {FunctionParallel} from './function_parallel.js';
diff --git a/ui/file_manager/file_manager/foreground/js/metadata/image_parsers.js b/ui/file_manager/file_manager/foreground/js/metadata/image_parsers.js
index 682b982..1252a7a 100644
--- a/ui/file_manager/file_manager/foreground/js/metadata/image_parsers.js
+++ b/ui/file_manager/file_manager/foreground/js/metadata/image_parsers.js
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import {MetadataParserLogger} from '../../../externs/metadata_worker_window.m.js';
+import {MetadataParserLogger} from '../../../externs/metadata_worker_window.js';
 
 import {ByteReader} from './byte_reader.js';
 import {ImageParser, MetadataParser} from './metadata_parser.js';
diff --git a/ui/file_manager/file_manager/foreground/js/metadata/metadata_dispatcher.js b/ui/file_manager/file_manager/foreground/js/metadata/metadata_dispatcher.js
index 8b7a4e0..73d8373 100644
--- a/ui/file_manager/file_manager/foreground/js/metadata/metadata_dispatcher.js
+++ b/ui/file_manager/file_manager/foreground/js/metadata/metadata_dispatcher.js
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import {MetadataParserLogger} from '../../../externs/metadata_worker_window.m.js';
+import {MetadataParserLogger} from '../../../externs/metadata_worker_window.js';
 
 import {ExifParser} from './exif_parser.js';
 import {Id3Parser} from './id3_parser.js';
diff --git a/ui/file_manager/file_manager/foreground/js/metadata/metadata_model.js b/ui/file_manager/file_manager/foreground/js/metadata/metadata_model.js
index 470a53dd..172f757 100644
--- a/ui/file_manager/file_manager/foreground/js/metadata/metadata_model.js
+++ b/ui/file_manager/file_manager/foreground/js/metadata/metadata_model.js
@@ -3,7 +3,7 @@
 // found in the LICENSE file.
 
 import {util} from '../../../common/js/util.m.js';
-import {VolumeManager} from '../../../externs/volume_manager.m.js';
+import {VolumeManager} from '../../../externs/volume_manager.js';
 
 import {ContentMetadataProvider} from './content_metadata_provider.js';
 import {ExternalMetadataProvider} from './external_metadata_provider.js';
diff --git a/ui/file_manager/file_manager/foreground/js/metadata/metadata_parser.js b/ui/file_manager/file_manager/foreground/js/metadata/metadata_parser.js
index 4f3ff53..7a42fcb 100644
--- a/ui/file_manager/file_manager/foreground/js/metadata/metadata_parser.js
+++ b/ui/file_manager/file_manager/foreground/js/metadata/metadata_parser.js
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import {MetadataParserLogger} from '../../../externs/metadata_worker_window.m.js';
+import {MetadataParserLogger} from '../../../externs/metadata_worker_window.js';
 
 import {ByteReader} from './byte_reader.js';
 
diff --git a/ui/file_manager/file_manager/foreground/js/metadata/mpeg_parser.js b/ui/file_manager/file_manager/foreground/js/metadata/mpeg_parser.js
index c6ac12c..4ce11b2 100644
--- a/ui/file_manager/file_manager/foreground/js/metadata/mpeg_parser.js
+++ b/ui/file_manager/file_manager/foreground/js/metadata/mpeg_parser.js
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import {MetadataParserLogger} from '../../../externs/metadata_worker_window.m.js';
+import {MetadataParserLogger} from '../../../externs/metadata_worker_window.js';
 
 import {ByteReader} from './byte_reader.js';
 import {MetadataParser} from './metadata_parser.js';
diff --git a/ui/file_manager/file_manager/foreground/js/metadata/multi_metadata_provider.js b/ui/file_manager/file_manager/foreground/js/metadata/multi_metadata_provider.js
index da34203..eaad675 100644
--- a/ui/file_manager/file_manager/foreground/js/metadata/multi_metadata_provider.js
+++ b/ui/file_manager/file_manager/foreground/js/metadata/multi_metadata_provider.js
@@ -6,7 +6,7 @@
 
 import {util} from '../../../common/js/util.m.js';
 import {VolumeManagerCommon} from '../../../common/js/volume_manager_types.m.js';
-import {VolumeManager} from '../../../externs/volume_manager.m.js';
+import {VolumeManager} from '../../../externs/volume_manager.js';
 
 import {ContentMetadataProvider} from './content_metadata_provider.js';
 import {ExternalMetadataProvider} from './external_metadata_provider.js';
diff --git a/ui/file_manager/file_manager/foreground/js/metadata/multi_metadata_provider_unittest.m.js b/ui/file_manager/file_manager/foreground/js/metadata/multi_metadata_provider_unittest.m.js
index 1ac6007..0ec2cd3 100644
--- a/ui/file_manager/file_manager/foreground/js/metadata/multi_metadata_provider_unittest.m.js
+++ b/ui/file_manager/file_manager/foreground/js/metadata/multi_metadata_provider_unittest.m.js
@@ -6,7 +6,7 @@
 
 import {reportPromise} from '../../../common/js/test_error_reporting.m.js';
 import {VolumeManagerCommon} from '../../../common/js/volume_manager_types.m.js';
-import {VolumeManager} from '../../../externs/volume_manager.m.js';
+import {VolumeManager} from '../../../externs/volume_manager.js';
 
 import {ContentMetadataProvider} from './content_metadata_provider.js';
 import {ExternalMetadataProvider} from './external_metadata_provider.js';
diff --git a/ui/file_manager/file_manager/foreground/js/metadata_box_controller.js b/ui/file_manager/file_manager/foreground/js/metadata_box_controller.js
index 16bd153..51c5f64 100644
--- a/ui/file_manager/file_manager/foreground/js/metadata_box_controller.js
+++ b/ui/file_manager/file_manager/foreground/js/metadata_box_controller.js
@@ -3,7 +3,7 @@
 // found in the LICENSE file.
 
 // #import {MetadataItem} from './metadata/metadata_item.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {FileMetadataFormatter} from './ui/file_metadata_formatter.js';
 // #import {QuickViewModel} from './quick_view_model.m.js';
 // #import {MetadataModel} from './metadata/metadata_model.js';
diff --git a/ui/file_manager/file_manager/foreground/js/mock_directory_model.js b/ui/file_manager/file_manager/foreground/js/mock_directory_model.js
index 1245025..c5b0c88 100644
--- a/ui/file_manager/file_manager/foreground/js/mock_directory_model.js
+++ b/ui/file_manager/file_manager/foreground/js/mock_directory_model.js
@@ -3,7 +3,7 @@
 // found in the LICENSE file.
 
 // clang-format off
-// #import {FilesAppDirEntry, FakeEntry} from '../../externs/files_app_entry_interfaces.m.js';
+// #import {FilesAppDirEntry, FakeEntry} from '../../externs/files_app_entry_interfaces.js';
 // #import {DirectoryModel} from './directory_model.m.js';
 // #import {FileFilter} from './directory_contents.m.js';
 // #import {NativeEventTarget as EventTarget} from 'chrome://resources/js/cr/event_target.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/mock_navigation_list_model.js b/ui/file_manager/file_manager/foreground/js/mock_navigation_list_model.js
index 33ca3c98..8d170a6 100644
--- a/ui/file_manager/file_manager/foreground/js/mock_navigation_list_model.js
+++ b/ui/file_manager/file_manager/foreground/js/mock_navigation_list_model.js
@@ -3,7 +3,7 @@
 // found in the LICENSE file.
 
 // clang-format off
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {NavigationModelVolumeItem, NavigationModelItem} from './navigation_list_model.m.js';
 // #import {NativeEventTarget as EventTarget} from 'chrome://resources/js/cr/event_target.m.js';
 // clang-format on
diff --git a/ui/file_manager/file_manager/foreground/js/navigation_list_model.js b/ui/file_manager/file_manager/foreground/js/navigation_list_model.js
index 8052b3e..5176685 100644
--- a/ui/file_manager/file_manager/foreground/js/navigation_list_model.js
+++ b/ui/file_manager/file_manager/foreground/js/navigation_list_model.js
@@ -6,9 +6,9 @@
 // #import {FolderShortcutsDataModel} from './folder_shortcuts_data_model.m.js';
 // #import {DirectoryModel} from './directory_model.m.js';
 // #import {AndroidAppListModel} from './android_app_list_model.m.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
-// #import {FilesAppEntry, FakeEntry} from '../../externs/files_app_entry_interfaces.m.js';
-// #import {VolumeInfo} from '../../externs/volume_info.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
+// #import {FilesAppEntry, FakeEntry} from '../../externs/files_app_entry_interfaces.js';
+// #import {VolumeInfo} from '../../externs/volume_info.js';
 // #import {TrashRootEntry} from '../../common/js/trash.js';
 // #import {util, str} from '../../common/js/util.m.js';
 // #import {FakeEntryImpl, VolumeEntry, EntryList} from '../../common/js/files_app_entry_types.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/navigation_list_model_unittest.m.js b/ui/file_manager/file_manager/foreground/js/navigation_list_model_unittest.m.js
index ba37a6e..b66025e6 100644
--- a/ui/file_manager/file_manager/foreground/js/navigation_list_model_unittest.m.js
+++ b/ui/file_manager/file_manager/foreground/js/navigation_list_model_unittest.m.js
@@ -13,7 +13,7 @@
 import {reportPromise, waitUntil} from '../../common/js/test_error_reporting.m.js';
 import {util} from '../../common/js/util.m.js';
 import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
-import {FilesAppEntry} from '../../externs/files_app_entry_interfaces.m.js';
+import {FilesAppEntry} from '../../externs/files_app_entry_interfaces.js';
 
 import {AndroidAppListModel} from './android_app_list_model.m.js';
 import {DirectoryModel} from './directory_model.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/navigation_uma.js b/ui/file_manager/file_manager/foreground/js/navigation_uma.js
index 7f95128..0efb34ba 100644
--- a/ui/file_manager/file_manager/foreground/js/navigation_uma.js
+++ b/ui/file_manager/file_manager/foreground/js/navigation_uma.js
@@ -4,7 +4,7 @@
 
 // clang-format off
 // #import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {metrics} from '../../common/js/metrics.m.js';
 // clang-format on
 
diff --git a/ui/file_manager/file_manager/foreground/js/path_component.js b/ui/file_manager/file_manager/foreground/js/path_component.js
index fdd35da1..2f9d478 100644
--- a/ui/file_manager/file_manager/foreground/js/path_component.js
+++ b/ui/file_manager/file_manager/foreground/js/path_component.js
@@ -3,7 +3,7 @@
 // found in the LICENSE file.
 
 // clang-format off
-// #import {FilesAppEntry, FakeEntry} from '../../externs/files_app_entry_interfaces.m.js';
+// #import {FilesAppEntry, FakeEntry} from '../../externs/files_app_entry_interfaces.js';
 // #import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
 // #import {util, str} from '../../common/js/util.m.js';
 // clang-format on
diff --git a/ui/file_manager/file_manager/foreground/js/providers_model.js b/ui/file_manager/file_manager/foreground/js/providers_model.js
index 2c894a0..7eaa67ff 100644
--- a/ui/file_manager/file_manager/foreground/js/providers_model.js
+++ b/ui/file_manager/file_manager/foreground/js/providers_model.js
@@ -5,7 +5,7 @@
 // clang-format off
 // #import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
 // #import {assert} from 'chrome://resources/js/assert.m.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // clang-format on
 
 /**
diff --git a/ui/file_manager/file_manager/foreground/js/providers_model_unittest.m.js b/ui/file_manager/file_manager/foreground/js/providers_model_unittest.m.js
index 0d6b404..0025688 100644
--- a/ui/file_manager/file_manager/foreground/js/providers_model_unittest.m.js
+++ b/ui/file_manager/file_manager/foreground/js/providers_model_unittest.m.js
@@ -10,7 +10,7 @@
 import {MockDirectoryEntry, MockFileSystem} from '../../common/js/mock_entry.m.js';
 import {reportPromise} from '../../common/js/test_error_reporting.m.js';
 import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
-import {VolumeManager} from '../../externs/volume_manager.m.js';
+import {VolumeManager} from '../../externs/volume_manager.js';
 
 import {ProvidersModel} from './providers_model.m.js';
 
diff --git a/ui/file_manager/file_manager/foreground/js/quick_view_controller.js b/ui/file_manager/file_manager/foreground/js/quick_view_controller.js
index a398b8f..2a98988 100644
--- a/ui/file_manager/file_manager/foreground/js/quick_view_controller.js
+++ b/ui/file_manager/file_manager/foreground/js/quick_view_controller.js
@@ -7,7 +7,7 @@
 // #import {MetadataItem} from './metadata/metadata_item.js';
 // #import {FileTasks} from './file_tasks.m.js';
 // #import {FilesQuickView} from '../elements/files_quick_view.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {MetadataBoxController} from './metadata_box_controller.m.js';
 // #import {FileListSelectionModel} from './ui/file_list_selection_model.js';
 // #import {TaskController} from './task_controller.m.js';
@@ -15,7 +15,7 @@
 // #import {MultiMenuButton} from './ui/multi_menu_button.js';
 // #import {ListContainer} from './ui/list_container.js';
 // #import {MetadataModel} from './metadata/metadata_model.js';
-// #import {CommandHandlerDeps} from '../../externs/command_handler_deps.m.js';
+// #import {CommandHandlerDeps} from '../../externs/command_handler_deps.js';
 // #import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
 // #import {ThumbnailLoader} from './thumbnail_loader.m.js';
 // #import {ImageLoaderClient} from 'chrome-extension://pmfjbimdmchhbnneeidfognadeopoehp/image_loader_client.js';
diff --git a/ui/file_manager/file_manager/foreground/js/quick_view_uma.js b/ui/file_manager/file_manager/foreground/js/quick_view_uma.js
index 1ed0ade..24ee278 100644
--- a/ui/file_manager/file_manager/foreground/js/quick_view_uma.js
+++ b/ui/file_manager/file_manager/foreground/js/quick_view_uma.js
@@ -3,7 +3,7 @@
 // found in the LICENSE file.
 
 // clang-format off
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
 // #import {metrics} from '../../common/js/metrics.m.js';
 // #import {DialogType} from './dialog_type.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/search_controller.js b/ui/file_manager/file_manager/foreground/js/search_controller.js
index 2fa052fa..8603ccc 100644
--- a/ui/file_manager/file_manager/foreground/js/search_controller.js
+++ b/ui/file_manager/file_manager/foreground/js/search_controller.js
@@ -3,8 +3,8 @@
 // found in the LICENSE file.
 
 // clang-format off
-// #import {EntryLocation} from '../../externs/entry_location.m.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {EntryLocation} from '../../externs/entry_location.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {FileManagerUI} from './ui/file_manager_ui.js';
 // #import {TaskController} from './task_controller.m.js';
 // #import {DirectoryModel} from './directory_model.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/task_controller.js b/ui/file_manager/file_manager/foreground/js/task_controller.js
index 82be55d..a9285bb 100644
--- a/ui/file_manager/file_manager/foreground/js/task_controller.js
+++ b/ui/file_manager/file_manager/foreground/js/task_controller.js
@@ -11,7 +11,7 @@
 // #import {DirectoryModel} from './directory_model.m.js';
 // #import {MetadataModel} from './metadata/metadata_model.js';
 // #import {FileManagerUI} from './ui/file_manager_ui.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {DialogType} from './dialog_type.m.js';
 // #import {strf, util, str} from '../../common/js/util.m.js';
 // #import {FileTasks} from './file_tasks.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/task_controller_unittest.m.js b/ui/file_manager/file_manager/foreground/js/task_controller_unittest.m.js
index 1c91ce9..2da980e 100644
--- a/ui/file_manager/file_manager/foreground/js/task_controller_unittest.m.js
+++ b/ui/file_manager/file_manager/foreground/js/task_controller_unittest.m.js
@@ -15,7 +15,7 @@
 import {util} from '../../common/js/util.m.js';
 import {VolumeManagerCommon} from '../../common/js/volume_manager_types.m.js';
 import {ProgressCenter} from '../../externs/background/progress_center.js';
-import {VolumeManager} from '../../externs/volume_manager.m.js';
+import {VolumeManager} from '../../externs/volume_manager.js';
 
 import {DialogType} from './dialog_type.m.js';
 import {DirectoryModel} from './directory_model.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/toolbar_controller.js b/ui/file_manager/file_manager/foreground/js/toolbar_controller.js
index b891b12..85374bbb 100644
--- a/ui/file_manager/file_manager/foreground/js/toolbar_controller.js
+++ b/ui/file_manager/file_manager/foreground/js/toolbar_controller.js
@@ -5,7 +5,7 @@
 // clang-format off
 // #import {FileListSelectionModel} from './ui/file_list_selection_model.js';
 // #import {A11yAnnounce} from './ui/a11y_announce.js';
-// #import {VolumeManager} from '../../externs/volume_manager.m.js';
+// #import {VolumeManager} from '../../externs/volume_manager.js';
 // #import {FileOperationManager} from '../../externs/background/file_operation_manager.js';
 // #import {DirectoryModel} from './directory_model.m.js';
 // #import {LocationLine} from './ui/location_line.js';
diff --git a/ui/file_manager/file_manager/foreground/js/ui/BUILD.gn b/ui/file_manager/file_manager/foreground/js/ui/BUILD.gn
index 413a54b..5106ca1 100644
--- a/ui/file_manager/file_manager/foreground/js/ui/BUILD.gn
+++ b/ui/file_manager/file_manager/foreground/js/ui/BUILD.gn
@@ -146,8 +146,8 @@
   deps = [
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_info",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/foreground/js:constants.m",
     "//ui/file_manager/file_manager/foreground/js:directory_model.m",
     "//ui/file_manager/file_manager/foreground/js:holding_space_util.m",
@@ -218,9 +218,9 @@
     "//ui/file_manager/file_manager/common/js:metrics.m",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
-    "//ui/file_manager/file_manager/externs:volume_info.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
+    "//ui/file_manager/file_manager/externs:volume_info",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:file_operation_manager",
     "//ui/file_manager/file_manager/foreground/js:constants.m",
     "//ui/file_manager/file_manager/foreground/js:directory_contents.m",
@@ -235,7 +235,7 @@
     "//ui/webui/resources/js/cr/ui:tree",
   ]
   visibility +=
-      [ "//ui/file_manager/file_manager/externs:command_handler_deps.m" ]
+      [ "//ui/file_manager/file_manager/externs:command_handler_deps" ]
 }
 
 js_unittest("directory_tree_unittest.m") {
@@ -280,8 +280,8 @@
     "//ui/file_manager/file_manager/common/js:file_type.m",
     "//ui/file_manager/file_manager/common/js:importer_common.m",
     "//ui/file_manager/file_manager/common/js:util.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:import_history",
     "//ui/file_manager/file_manager/foreground/js:list_thumbnail_loader.m",
     "//ui/file_manager/file_manager/foreground/js/metadata:metadata_model",
@@ -353,7 +353,7 @@
     ":search_box",
     "//ui/file_manager/file_manager/common/js:util.m",
     "//ui/file_manager/file_manager/common/js:volume_manager_types.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/foreground/elements:files_password_dialog",
     "//ui/file_manager/file_manager/foreground/elements:files_toast",
     "//ui/file_manager/file_manager/foreground/elements:files_tooltip",
@@ -370,7 +370,7 @@
     "//ui/webui/resources/js/cr/ui:splitter",
   ]
   visibility +=
-      [ "//ui/file_manager/file_manager/externs:command_handler_deps.m" ]
+      [ "//ui/file_manager/file_manager/externs:command_handler_deps" ]
 }
 
 js_library("file_metadata_formatter") {
@@ -396,9 +396,9 @@
     "//ui/file_manager/file_manager/common/js:file_type.m",
     "//ui/file_manager/file_manager/common/js:importer_common.m",
     "//ui/file_manager/file_manager/common/js:util.m",
-    "//ui/file_manager/file_manager/externs:entry_location.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:entry_location",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/externs/background:import_history",
     "//ui/file_manager/file_manager/foreground/js:file_list_model.m",
     "//ui/file_manager/file_manager/foreground/js:list_thumbnail_loader.m",
@@ -427,8 +427,8 @@
     "table:table_list",
     "//ui/file_manager/file_manager/common/js:file_type.m",
     "//ui/file_manager/file_manager/common/js:util.m",
-    "//ui/file_manager/file_manager/externs:entry_location.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
+    "//ui/file_manager/file_manager/externs:entry_location",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
     "//ui/file_manager/file_manager/foreground/js/metadata:metadata_model",
     "//ui/webui/resources/js:assert.m",
     "//ui/webui/resources/js:cr.m",
@@ -553,8 +553,8 @@
     ":list_container",
     "//ui/file_manager/file_manager/common/js:metrics.m",
     "//ui/file_manager/file_manager/common/js:util.m",
-    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces.m",
-    "//ui/file_manager/file_manager/externs:volume_manager.m",
+    "//ui/file_manager/file_manager/externs:files_app_entry_interfaces",
+    "//ui/file_manager/file_manager/externs:volume_manager",
     "//ui/file_manager/file_manager/foreground/elements:files_tooltip",
     "//ui/file_manager/file_manager/foreground/js:path_component.m",
     "//ui/webui/resources/js/cr:event_target.m",
@@ -601,7 +601,7 @@
   deps = [
     "//ui/file_manager/file_manager/common/js:progress_center_common.m",
     "//ui/file_manager/file_manager/common/js:util.m",
-    "//ui/file_manager/file_manager/externs:progress_center_panel.m",
+    "//ui/file_manager/file_manager/externs:progress_center_panel",
     "//ui/webui/resources/js:assert.m",
   ]
 }
diff --git a/ui/file_manager/file_manager/foreground/js/ui/banners.js b/ui/file_manager/file_manager/foreground/js/ui/banners.js
index ff05a477..4047c84 100644
--- a/ui/file_manager/file_manager/foreground/js/ui/banners.js
+++ b/ui/file_manager/file_manager/foreground/js/ui/banners.js
@@ -10,8 +10,8 @@
 import {str, strf, util} from '../../../common/js/util.m.js';
 import {VolumeManagerCommon} from '../../../common/js/volume_manager_types.m.js';
 import {xfm} from '../../../common/js/xfm.m.js';
-import {VolumeInfo} from '../../../externs/volume_info.m.js';
-import {VolumeManager} from '../../../externs/volume_manager.m.js';
+import {VolumeInfo} from '../../../externs/volume_info.js';
+import {VolumeManager} from '../../../externs/volume_manager.js';
 import {constants} from '../constants.m.js';
 import {DirectoryModel} from '../directory_model.m.js';
 import {HoldingSpaceUtil} from '../holding_space_util.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/ui/directory_tree.js b/ui/file_manager/file_manager/foreground/js/ui/directory_tree.js
index 6b48c60..2aa5a062 100644
--- a/ui/file_manager/file_manager/foreground/js/ui/directory_tree.js
+++ b/ui/file_manager/file_manager/foreground/js/ui/directory_tree.js
@@ -14,9 +14,9 @@
 import {str, util} from '../../../common/js/util.m.js';
 import {VolumeManagerCommon} from '../../../common/js/volume_manager_types.m.js';
 import {FileOperationManager} from '../../../externs/background/file_operation_manager.js';
-import {FilesAppDirEntry} from '../../../externs/files_app_entry_interfaces.m.js';
-import {VolumeInfo} from '../../../externs/volume_info.m.js';
-import {VolumeManager} from '../../../externs/volume_manager.m.js';
+import {FilesAppDirEntry} from '../../../externs/files_app_entry_interfaces.js';
+import {VolumeInfo} from '../../../externs/volume_info.js';
+import {VolumeManager} from '../../../externs/volume_manager.js';
 import {constants} from '../constants.m.js';
 import {FileFilter} from '../directory_contents.m.js';
 import {DirectoryModel} from '../directory_model.m.js';
diff --git a/ui/file_manager/file_manager/foreground/js/ui/file_grid.js b/ui/file_manager/file_manager/foreground/js/ui/file_grid.js
index b5d4bbc..9fdf603 100644
--- a/ui/file_manager/file_manager/foreground/js/ui/file_grid.js
+++ b/ui/file_manager/file_manager/foreground/js/ui/file_grid.js
@@ -15,8 +15,8 @@
 import {importer} from '../../../common/js/importer_common.m.js';
 import {str, util} from '../../../common/js/util.m.js';
 import {importerHistoryInterfaces} from '../../../externs/background/import_history.js';
-import {FilesAppEntry} from '../../../externs/files_app_entry_interfaces.m.js';
-import {VolumeManager} from '../../../externs/volume_manager.m.js';
+import {FilesAppEntry} from '../../../externs/files_app_entry_interfaces.js';
+import {VolumeManager} from '../../../externs/volume_manager.js';
 import {ListThumbnailLoader} from '../list_thumbnail_loader.m.js';
 import {MetadataModel} from '../metadata/metadata_model.js';
 
diff --git a/ui/file_manager/file_manager/foreground/js/ui/file_manager_ui.js b/ui/file_manager/file_manager/foreground/js/ui/file_manager_ui.js
index 04c5ed6..b6c1aeed 100644
--- a/ui/file_manager/file_manager/foreground/js/ui/file_manager_ui.js
+++ b/ui/file_manager/file_manager/foreground/js/ui/file_manager_ui.js
@@ -13,7 +13,7 @@
 
 import {str, strf, util} from '../../../common/js/util.m.js';
 import {AllowedPaths} from '../../../common/js/volume_manager_types.m.js';
-import {VolumeManager} from '../../../externs/volume_manager.m.js';
+import {VolumeManager} from '../../../externs/volume_manager.js';
 import {FilesPasswordDialog} from '../../elements/files_password_dialog.js';
 import {FilesToast} from '../../elements/files_toast.js';
 import {FilesTooltip} from '../../elements/files_tooltip.js';
diff --git a/ui/file_manager/file_manager/foreground/js/ui/file_table.js b/ui/file_manager/file_manager/foreground/js/ui/file_table.js
index 7dfcda90..1d689d0 100644
--- a/ui/file_manager/file_manager/foreground/js/ui/file_table.js
+++ b/ui/file_manager/file_manager/foreground/js/ui/file_table.js
@@ -13,9 +13,9 @@
 import {importer} from '../../../common/js/importer_common.m.js';
 import {str, strf, util} from '../../../common/js/util.m.js';
 import {importerHistoryInterfaces} from '../../../externs/background/import_history.js';
-import {EntryLocation} from '../../../externs/entry_location.m.js';
-import {FilesAppEntry} from '../../../externs/files_app_entry_interfaces.m.js';
-import {VolumeManager} from '../../../externs/volume_manager.m.js';
+import {EntryLocation} from '../../../externs/entry_location.js';
+import {FilesAppEntry} from '../../../externs/files_app_entry_interfaces.js';
+import {VolumeManager} from '../../../externs/volume_manager.js';
 import {FileListModel} from '../file_list_model.m.js';
 import {ListThumbnailLoader} from '../list_thumbnail_loader.m.js';
 import {MetadataModel} from '../metadata/metadata_model.js';
diff --git a/ui/file_manager/file_manager/foreground/js/ui/file_table_list.js b/ui/file_manager/file_manager/foreground/js/ui/file_table_list.js
index b8e5a09..c02378c 100644
--- a/ui/file_manager/file_manager/foreground/js/ui/file_table_list.js
+++ b/ui/file_manager/file_manager/foreground/js/ui/file_table_list.js
@@ -11,8 +11,8 @@
 
 import {FileType} from '../../../common/js/file_type.m.js';
 import {str, strf, util} from '../../../common/js/util.m.js';
-import {EntryLocation} from '../../../externs/entry_location.m.js';
-import {FilesAppEntry} from '../../../externs/files_app_entry_interfaces.m.js';
+import {EntryLocation} from '../../../externs/entry_location.js';
+import {FilesAppEntry} from '../../../externs/files_app_entry_interfaces.js';
 import {MetadataModel} from '../metadata/metadata_model.js';
 
 import {A11yAnnounce} from './a11y_announce.js';
diff --git a/ui/file_manager/file_manager/foreground/js/ui/location_line.js b/ui/file_manager/file_manager/foreground/js/ui/location_line.js
index c3875c29..16cbf7d 100644
--- a/ui/file_manager/file_manager/foreground/js/ui/location_line.js
+++ b/ui/file_manager/file_manager/foreground/js/ui/location_line.js
@@ -6,8 +6,8 @@
 
 import {metrics} from '../../../common/js/metrics.m.js';
 import {util} from '../../../common/js/util.m.js';
-import {FakeEntry} from '../../../externs/files_app_entry_interfaces.m.js';
-import {VolumeManager} from '../../../externs/volume_manager.m.js';
+import {FakeEntry} from '../../../externs/files_app_entry_interfaces.js';
+import {VolumeManager} from '../../../externs/volume_manager.js';
 import {FilesTooltip} from '../../elements/files_tooltip.js';
 import {PathComponent} from '../path_component.m.js';
 
diff --git a/ui/file_manager/file_manager/foreground/js/ui/progress_center_panel.js b/ui/file_manager/file_manager/foreground/js/ui/progress_center_panel.js
index c5b902b..465420b6 100644
--- a/ui/file_manager/file_manager/foreground/js/ui/progress_center_panel.js
+++ b/ui/file_manager/file_manager/foreground/js/ui/progress_center_panel.js
@@ -6,7 +6,7 @@
 
 import {ProgressCenterItem, ProgressItemState, ProgressItemType} from '../../../common/js/progress_center_common.m.js';
 import {str, strf} from '../../../common/js/util.m.js';
-import {ProgressCenterPanelInterface} from '../../../externs/progress_center_panel.m.js';
+import {ProgressCenterPanelInterface} from '../../../externs/progress_center_panel.js';
 
 /**
  * Progress center panel.
diff --git a/ui/file_manager/file_manager/manifest.json b/ui/file_manager/file_manager/manifest.json
index 26cc08a..23a64b9 100644
--- a/ui/file_manager/file_manager/manifest.json
+++ b/ui/file_manager/file_manager/manifest.json
@@ -164,13 +164,13 @@
     "common/js/volume_manager_types.m.js",
     "common/js/xfm.m.js",
     "externs/background/background_base.js",
-    "externs/drive_dialog_controller.m.js",
-    "externs/entry_location.m.js",
-    "externs/files_app_entry_interfaces.m.js",
-    "externs/progress_center_panel.m.js",
-    "externs/volume_info.m.js",
-    "externs/volume_info_list.m.js",
-    "externs/volume_manager.m.js",
+    "externs/drive_dialog_controller.js",
+    "externs/entry_location.js",
+    "externs/files_app_entry_interfaces.js",
+    "externs/progress_center_panel.js",
+    "externs/volume_info.js",
+    "externs/volume_info_list.js",
+    "externs/volume_manager.js",
     "externs/background/crostini.js",
     "externs/background/drive_sync_handler.js",
     "externs/background/duplicate_finder.js",