Right click a message. Notice the Forward and Forward As >... menus are not aligned the same. The Forward as (and others with submenu) are a few pixels more to the left than they should.

nightly 111, correct?

Yes. But I haven't checked beta.

On Mac, pretty sure I'm not seeing this with current nightly. And I'm not seeing it with 110.0b4. I didn't test the 111.0b1 candidate.

Still there for linux daily.

I'm seeing this, too on Daily 112.0a1 (2023-02-19) (64-bit), Win10 - see my screenshot below.
And Ignore Thread, Ignore Subthread, and Watch Thread are totally off, with a negative indent of about 1 cm, which is about the space otherwise reserved for icons I guess.

Richard, any insights?

Screenshot: sub-menu items slightly offset to the right, and Ignore Thread & Co. with negative indent

As a sidenote, it's a bit surprising why there should be so much whitespace on the left side if there's not a single icon. But if it helps to add icons later on, then so be it!

(In reply to Wayne Mery (:wsmwk) from comment #3)

Created attachment 9318342 [details]
Screen Shot Mac.png

On Mac, pretty sure I'm not seeing this with current nightly. And I'm not seeing it with 110.0b4. I didn't test the 111.0b1 candidate.

If that's what you're seeing on the Mac, then that's even more broken. No indication of sub-menus at all because of missing arrows on the right.

Pushed by martin@humanoids.be:
https://hg.mozilla.org/comm-central/rev/3df2a3683765
Don't use class="menuitem-iconic" together with type="checkbox". r=freaktechnik

Awesome! Thank you Richard!

Do you think this will also fix Wayne's Mac problem where there are no sub-menu arrows on the <menu> items?

I see the arrows with and without patch. Let's wait at tomorrows Daily if Wayne sees the arrows.

Comment on attachment 9318764 [details]
Bug 1815607 - Don't use class="menuitem-iconic" together with type="checkbox". r=#thunderbird-front-end-reviewers

[Approval Request Comment]
Regression caused by (bug #): [Supernova]
User impact if declined: not aligned menuitems
Testing completed (on c-c, etc.): on c-c
Risk to taking this patch (and alternatives if risky): low

Comment on attachment 9318764 [details]
Bug 1815607 - Don't use class="menuitem-iconic" together with type="checkbox". r=#thunderbird-front-end-reviewers

[Triage Comment]
Approved for beta

Here's another one - Richard, would you be willing to check around in other context menus and/or regular menus?

This one is fixed by my patch.

Thunderbird 111.0b1:
https://hg.mozilla.org/releases/comm-beta/rev/1a6a704c18d2