Checked on testwiki - my IP user doesn't receive anything. When I check https://test.wikipedia.org/w/api.php?action=query&meta=userinfo&uiprop=hasmsg shows 0. I checked for a signed up user - all works as expected on testwiki, including the orange bar.

On betalabs I see the following after I log out. But if I (without logging in) would switch to any other page - there will no indication that I have any notifications.

In T295429#7499198, @Tgr wrote:

Maybe some extension/feature only enabled on testwiki is interfering? No idea what that could be.

LiquidThreads maybe?

And maybe 359607fe9f17 is related:

                // If the user isn't using LQT on their talk page, bail out
                if ( !LqtDispatch::isLqtPage( $usertalk_t ) ) {
-                       return true;
+                       return false;
                }

Could you try on test2wiki, it doesnt have LQ https://test2.wikipedia.org/wiki/Special:Version

It's installed but at Special:Version it's spelled "Liquid Threads" instead of "LiquidThreads". And I get no message bar. You can see the full list at https://noc.wikimedia.org/conf/highlight.php?file=InitialiseSettings.php. EIther wmgUseLiquidThreads or wmgLiquidThreadsFrozen force the extension to load.

Thanks for the thorough investigation @suffusion_of_yellow! You are correct, returning false from the GetNewMessagesAlert hook when the user does not use LiquidThreads seems like a bug.

@suffusion_of_yellow -- thanks for filing this task. I'm pinging @ovasileva from the team that worked on adding the bar to mobile so that they see this issue.

We can take a look

Change 739387 had a related patch set uploaded (by Gergő Tisza; author: Gergő Tisza):

[mediawiki/extensions/LiquidThreads@master] Fix new message alerts for users with non-LQT talk pages

https://gerrit.wikimedia.org/r/739387

Change 739387 merged by jenkins-bot:

[mediawiki/extensions/LiquidThreads@master] Fix new message alerts for users with non-LQT talk pages

https://gerrit.wikimedia.org/r/739387

I tried again on testwiki, enwiktionary, and enwikinews, and got an alert every time. Thanks for fixing this! Now where do we talk about disabling LiquidThreads on all WMF wikis?

Test Result - Beta

Status: ✅ PASS
Environment: beta
OS: macOS Monterey
Browser: Chrome
Device: MBP
Emulated Device:NA

Test Artifact(s):

QA Steps

Using an account, leave a message on your own IP's talk page on beta
✅ AC1: While logged out, visit https://en.wikipedia.beta.wmflabs.org/wiki/api.php?action=query&meta=userinfo&uiprop=hasmsg to verify that step 1 worked

✅ AC2: While still logged out, open your network monitor and visit https://test.wikipedia.org/w/index.php?title=Talk:Foo&action=edit&safemode=1 or https://test.m.wikipedia.org/w/index.php?title=Talk:Foo&action=edit&safemode=1. Verify a "you have new messages" alert (Orange/Peach Bar of Doom) is shown.

In T295429#7557879, @suffusion_of_yellow wrote:

... Now where do we talk about disabling LiquidThreads on all WMF wikis?

T187487: LiquidThreads: code stewardship review