User Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:87.0) Gecko/20100101 Firefox/87.0

Steps to reproduce:

Since update to 87.0b2, Min/Max/Close do not appear.
It was present in previous B versions, though this did previously occur under beta for 86, I did not track the version it happened under at the time as it was resolved in an following update.

"Menu Bar" is not/has never been displayed.
Density is Compact.
There are no titlebar addons in effect.

Ran in Safemode, and with Reset browser data, still no Min/Max/Close visible.

Actual results:

No Min/Max/Close

Expected results:

Min/Max/Close should be visible and available

87.0b3 still exhibits no min/max/close on the browser window.
Popup windows (such as the "About" screen, or the Developer Tools) DO show the appropriate caption buttons.
Tabs still show "x" on the right, and New Tab "+" is visible.

(As a correction to the typo creating this ticket, the OS is Windows 7 SP1 x64 Ultimate, currently and fully updated)

87.0b4 Continues with no change.

Hi Michael,

Are you using the default theme? Because if not, this would be a duplicate of bug#1694734 and the problem is already being treated.

I can then confirm that this is indeed a "duplicate" of that issue, after reviewing it (but it didn't show up as a listed "seems like" when I opened this case).
While I'm not using any 3rd Party Themes or extensions/customization's, I am using the built in "Dark" option, not "Default"

In testing, only "Default" and "light" show the caption controls.

Thank you for spotting the potential issue similarity and the inquiry.

As another note: After observing what happens when changing the built in theme ... the controls ARE present. They're just utterly invisible.

Hi Michael,

Thanks for the reply. I'm glad they are there, now you can kind of find them while waiting for the fix. I advise you to follow the other bug to know when this will be fixed.

Kind regards, Flor.