PieterL

While the steps you provide may work in some cases, in this case the issue was the StartupWMClass in the responses above and it is fixed. This topic should be closed.

Great, it is fixed! So, I should've found out using Looking Glass as per https://sourceforge.net/p/ubuntuzilla/bugs/51/: The StartupWMClass field in /usr/share/applications/firefox-mozilla-build.desktop in the deb is "Firefox", but when I run Looking Glass in Wayland and look at the window it says that its WMClass is "firefox", not the lower-case "f".

I tried the ubuntu community. Hope they don't just bounce me back here :-) https://ubuntuforums.org/showthread.php?t=2487636&p=14146572#post14146572

Hi, a very cosmetic nitty picky thing: I see that on ubuntu 23.04 firefox comes with a pixmap used in the desktop file. It is shown correctly in the application list and in my favourites in the dock, but not in the open window list. See red arrows. Any clue how to fix this minor thing?

Great! Thanks for this and thanks for keeping mozilla product available without flatpak or snap ;-)

These pages on sourceforge refer to the ubuntuforums for support. Behind this link going to "Got Questions?" for example. But the ubuntuzilla support forum on ubuntu forums is an ancient and readonly archive. Where is help organized for this project?