User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:56.0) Gecko/20100101 Firefox/56.0

Steps to reproduce:

Launched Thunderbird. Thunderbird is configured to ask for my master password on launch.

Actual results:

Master password prompt appears twice in quick succession. These prompts are sheets on macOS, so only one is visible at a time. The second sheet looks like it’s the key window but doesn’t accept any keyboard or mouse events.

At this point, the rest of the UI is inaccessible. I can see an animating spinner on the main tab, and I can even open a new tab by going to Thunderbird ‣ About and clicking on Release Notes, but otherwise all I can do is force-quit Thunderbird.

Expected results:

The frontmost sheet should accept keyboard and mouse events.

In the past, I have often seen something similar where a prompt appears above a prompt that has keyboard focus. But the additional prompts always showed up as separate modal dialogs, so I would switch to another application and back and the topmost prompt would have focus, no problem. What seems to be different now is that the prompts are all sheets, so I have no opportunity to fix the focus.

I’m reproducing this issue in build 20210212193837. I had just upgraded from build 20210128005905, which did not reproduce this issue.

This may be a red herring, but I’m only able to reproduce this issue when launching Thunderbird normally. When I launch Thunderbird from the command line (/Applications/Earlybird.app/Contents/MacOS/thunderbird-bin -no-remote -P), I see an additional prompt to save space by clearing trash, but none of the prompts end up locking up the UI.

Thanks Minh, well-described for Mac. You shouldn't even get more than one master password prompt, but it seems that problem is stubbornly returning.

Magnus, any hints? Anyone we could CC who knows more about master passwords functionality?

Can you try with a daily build as well?
On mac it's expected that there may be multiple prompts, as we haven't been able to fix bug 1612456 yet.

Yes, I’m used to seeing multiple prompts, but this is the first time I’ve started seeing a UI deadlock as a result. There seems to be a race condition because sometimes I get more prompts than other times. Sometimes they do come up as modal dialogs, as before, but the Window menu lists some extra password prompts that aren’t visible and that I can’t get to. I can open some windows like the address book, but anything related to the Mail & Newsgroups window is blocked on these master password prompts. The Quit menu item doesn’t work, but Quit from the dock menu sometimes does.

The issue still reproduces in the latest daily of 88.0a1 (2021-02-27).

As long as the master password prompt is a sheet on macOS, every subsequent prompt causes the preceding prompt to momentarily slide up and hide, only to return after the subsequent prompt has been dismissed. This might be by design, but it might be contributing to the focus issue.

(In reply to Minh Nguyễn from comment #2)

This may be a red herring, but I’m only able to reproduce this issue when launching Thunderbird normally. When I launch Thunderbird from the command line (/Applications/Earlybird.app/Contents/MacOS/thunderbird-bin -no-remote -P), I see an additional prompt to save space by clearing trash, but none of the prompts end up locking up the UI.

I think it was a red herring. On the bright side, I’ve discovered a more reliable workaround, which is to start Thunderbird in offline mode. I still get about five master password prompts, but they all queue up nicely without interrupting each other.

bug 530608 ?

Minh, do you still see this with a recent nightly?

So far in Thunderbird 102 I’ve stopped seeing this issue at all.