User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/111.0

Steps to reproduce:

I used Thunderbird 111.0a1 (2022-1-20) to (2022-2-13) on Wayland in Plasma 5.26.5 in a Fedora 37 KDE Plasma installation. I right-clicked on emails in the folders of an IMAP account or Local Folders without having left-clicked on them or otherwise selected them first. I left-clicked on emails in lists and then right-clicked on them. I right-clicked on different emails than the ones I left-clicked on right before then.

Actual results:

Right-clicking on emails in lists didn't show their context menus when they hadn't been selected first. Right-clicking on emails in lists showed their context menus when they had been left-clicked first in Thunderbird 111.0a1. Right-clicking on emails other than the one previously selected by left-clicking on it showed a context menu that when selected acted on the previously selected email instead of the email under the cursor. This problem didn't happen with 111.0a1 (2023-1-18) and earlier. I guess the problem is related to the interface changes which were merged 2023-1-19 https://hg.mozilla.org/comm-central/pushloghtml?fromchange=76f62fd3a78092592457e19dbc6e59f87c4f084d&tochange=5abcc1359eb7d4122f958a823e29b43de5f60b2e as described at https://thunderbird.topicbox.com/groups/daily/T7df1556699d655bb/please-read-thunderbird-supernova-alpha-release I waited until February 14 to report this problem as requested on that page.

Expected results:

Right-clicking on emails in lists should have shown their context menus when they hadn't been selected first by left-clicking on them. Right-clicking on emails other than the one previously selected by left-clicking on it should have shown a context menu that when selected acted on the email under the cursor.

Also on Mac.

(In reply to Matt Fagnani from comment #0)

I waited until February 14 to report this problem as requested on that page.

Thanks Matt for waiting so patiently and filing this! This bug is happening exactly as you described.
I've added your simple scenario (no messages selected, no context menu on right-click) to Bug 1816741 Comment 0.
I'll resolve your bug as a duplicate of that so that it can get fixed. Kindly use line breaks, numbering, bullets, and/or a) b) c) when describing several scenarios with different outcomes: having them all inline makes them a bit hard to disentangle... ;-)
Again, thank you for caring for Thunderbird!

Oh OK. Thanks. I bisected the problems I described which started with 111.0a1 2023-1-19 using mozregression --app thunderbird --good 2023-1-18 --bad 2023-1-19 --persist /tmp/mozregression -p ~/.thunderbird/9hcim5o9.default --profile-persistence reuse

The first bad revision had a pushlog with the 282 merge changesets for the interface changes I guessed were involved.
3:01.24 INFO: Narrowed integration regression window from [76f62fd3, 45322ce6] (3 builds) to [76f62fd3, 5abcc135] (2 builds) (~1 steps left)
3:01.24 INFO: No more integration revisions, bisection finished.
3:01.24 INFO: Last good revision: 76f62fd3a78092592457e19dbc6e59f87c4f084d
3:01.24 INFO: First bad revision: 5abcc1359eb7d4122f958a823e29b43de5f60b2e
3:01.24 INFO: Pushlog:
https://hg.mozilla.org/comm-central/pushloghtml?fromchange=76f62fd3a78092592457e19dbc6e59f87c4f084d&tochange=5abcc1359eb7d4122f958a823e29b43de5f60b2e