User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:86.0) Gecko/20100101 Firefox/86.0

Steps to reproduce:

1. In Thunderbird, "Reply" to email.
2. Copy and cut entire email (for use in external document).
3. Try to close the email window. "Save Message" dialog pops up to save message as draft or to "Discard" (with the "D" underlined).
4. The "D" on the keyboard does not discard, requiring a click on the button, "Discard changes."

Actual results:

I clicked on "Discard changes."

Expected results:

Pressing "D" should close the window.

Why open a reply to select all the contents and cut or copy them?

The key combination is Alt+D.

I needed to copy an email. Ctrl-A did not include the header, the from and date/time. In a reply window, it is nicely copied. So maybe that is a UI bug to report in another category?

Thanks for telling me about Alt-D - I haven't used Thunderbird since the unified Mozilla package was split up.

Alice, could you find the regression window?

(In reply to WaltS48 [:walts48] from comment #1)

Why open a reply to select all the contents and cut or copy them?

Not needed for these STR, but otherwise legitimate use case. Maybe just to have the "On ..., XY wrote" header included.

The key combination is Alt+D.

That's not quite true. Plain "D" has worked since time immemorial in this dialog (still works in TB 68), by design - probably when focus is on one of several buttons (or perhaps even when one button is default button, or perhaps always on those dialog-type little alerts), plain access key is supposed to work here, and this is a regression.

Plain "S" for "Save" still works on TB 78, why not "D" for "Discard"? That's inconsistent. Alt+D is quite a workflow breaker (clumsy), and it adds nothing. Worse, in TB 88, neither Alt+D nor D do the trick. Something is definitely broken here.

Ironically, plain "D" will work as an access key after you focus the Discard button, i.e. when you could just press Enter instead... :-/

Maybe the same as bug 1625632.

Going to dupe.