Can you restore Firefox to the default theme to see if it makes a difference. Let me boot to Win 7 and check.

I could not replicate the issue. see screenshots Have tried running Firefox in Safe Mode? https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode#w_how-to-start-firefox-in-4troubleshoot-modesf5safe-modesf

screenshot --> https://paste.opensuse.org/82254147

......

The problem does not happen with the built-in default theme. But it seems to happen with any theme that features a bitmap (image).

Of course they are Firefox themes, omg. I have disabled all extensions, with no effect. So the problem is inside Firefox itself. Now it started happening on my pinned Google Calendar. Gmail is ok, Calendar in the 2nd tab triggers the bug.

Provide the name of that theme you're using and I'll see if I can replicate the issue.

Found it. Let me go try it on Win 7. I would think if there's an issue with theme you would need to contact the creator.

Japanese Tattoo by enguyen-1364597692.39 https://addons.mozilla.org/en-US/firefox/addon/japanese-tattoo/?utm_source=addons.mozilla.org&utm_medium=referral&utm_content=search

Not able to replicate the issue. see screenshot ---> https://paste.opensuse.org/5971996 You are just special.  ;-)) Do you have the same issue under a different Windows account?

It happened with "Japanese Tattoo", "simple solid teal time" and "Two little birds". It will occur with tons of other themes as I have written.

This is pointless if no developer reads this :( The bug is hard to reproduce and probably depends on open tabs. But that does not mean that the bug does not exist!

I might be better digging through source code and compiling it myself...

Are those (.titlebar-buttonbox-container) buttons present if you check this with the Browser Toolbox?

• https://developer.mozilla.org/en-US/docs/Tools/Browser_Toolbox

Hello cor-el. I am sorry. Gmail completedly stopped working in my Firefox so I was forced to quit it and start anew. Oops I wanted to write that the bug does not manifest anymore but it does.

Those buttons are indeed present. Though sometimes they are invisible. When they are "invisible", they work as expected when clicked. Their tooltip displays on mouseover after a while. And I can see their colored shadow outside Firefox windows's frame (everything pertaining to Aero on).

So either the buttons are not rendered or (more probably) they are rendered and later replaced by a theme's bitmap.

Attaching a screenshot. Hopefully relevant.

Maybe you can try to give them a higher z-index or try background: unset !important; or change the background otherwise.

Tried changing that z-index, but the Toolbox did not allow me to. I tried to find the background rule but I could not find it. Please see the attached picture. This is the best I have been able to find (right middle pane):

• --lwt-header-image
• --lwt-accent-color

After disabling both of these, the buttons reappeared on https://www.o2tv.cz/. Bitmap and color fill were gone, that part of the window was translucent. But the buttons reappeared.