Steps to reproduce:

1. Thunderbird is running
2. Super-L to lock screen of laptop/Linux; see lock screen
3. Close lid of laptop
4. Come back 15+ minutes later
5. Open lid
6. Log in to OS
7. See Thunderbird main window
8. Click on Get Messages button
9. Nothing happens
10. Wait 15+ minutes; sometimes I've waited hours
11. No new messages fetched on any account (I have 3 accounts, all using IMAP)
12. Quit out of Thunderbird
13. Launch Thunderbird again
14. New messages are fetched right away

I'm using Thunderbird 101.0b1 (64-bit) on openSUSE Tumbleweed KDE Linux. I am using a VPN. Ethernet and VPN connections de-activate when I log out, re-activate automatically when I log in again.

Actual results:

No new messages fetched until quit and re-launch Thunderbird

Expected results:

New messages should have been fetched without having to restart Thunderbird

I can also confirm this issue (albeit on an older version of Thunderbird) when using hibernation on Windows.

Bill, are you seeing this with a current beta version?

I have changed distro twice since filing, now I'm on Solus 4.3 Budgie. On TB 105.0b2 (64-bit), I am not seeing this bug.

Justin, are you still seeing this?

I just updated to TB 102, so I'll let you know if it continues to happen there. If so, I'll see about getting a beta installation up and running to test.

It looks like after hibernation the "check every 10 minutes" works, but a connection to the server is not reestablished ("server notifications," whatever the technical name for it is) until maximizing TB, which, as far as I can tell, leads to a manual refresh of the inbox (presumably somehow different from the interval ones), so the instant notifications start again.

Reading more thoroughly, I suppose this is different from the original issue, as I can manually retrieve messages without closing and reopening Thunderbird; it's perhaps more of a feature request to detect resuming from sleep/hibernation and reestablish a connection to mail servers for quicker notifications?

I think I have to retract my previous comment. I think I am still seeing this problem, intermittently. I'm now on Solus 4.3 Budgie with TB 105.0b4 (64-bit).

Yes, confirmed, still seeing this problem.

Maybe forgot to mention: I am using a VPN. Not sure if that is affecting the issue. VPN re-connects fine after Ethernet comes up, but then TB may not fetch new messages. After some hours, if I quit TB and then launch it again, suddenly it fetches 5 or 6 new messages that had arrived much earlier.

(In reply to Bill Dietrich from comment #8)

Yes, confirmed, still seeing this problem.

Maybe forgot to mention: I am using a VPN. Not sure if that is affecting the issue. VPN re-connects fine after Ethernet comes up, but then TB may not fetch new messages. After some hours, if I quit TB and then launch it again, suddenly it fetches 5 or 6 new messages that had arrived much earlier.

Please perform a test:
Switch off VPN or create a tunnel for Thunderbird, so it does not use it.
Run Thunderbird for a reasonable length of time which may be several hours.
Provide info on whether everything works ok when you switch off VPN.

Bill?

Now I'm on MX Linux, I think I am not seeing this bug.

Thanks for theupdate.
WFM per comment 11

Happened again yesterday, with VPN running. I think VPN is a factor. TB 108.0b1 (64-bit) on MX Linux 21 with kernel 5.18. VPN is using OpenVPN.

Still happens, on Linux Nobara 37, with TB 112.0b7 (64-bit), when using a VPN. Just launch TB, see msgs, then turn VPN to other state (off to on, or on to off). Then from some other device, send an email to the account TB is showing. The message will not be displayed.

Still happens on TB 114.0b4 (64-bit) on Nobara Linux.

This is high-priority, to me. I can't trust my email client any more, it may be wedged instead of showing me new messages. Will this be fixed in 115 ? I hope so.

Still happening, on 125.0b4 on CachyOS Linux. I can't trust my email because of this, it is failing to fetch new messages until I quit and launch again.