I have an issue related to pinned tabs that I hope someone can help me with. Using Firefox 61.0.1 on Windows 10. I recently installed an add-on called AutoMute that mutes all tabs by default, a side-effect of which is that the audio-muted overlay icon shows in ALL tabs. I managed to find this css and added it to userchrome.css, which is supposed to remove the icon from ALL the tabs: .tabbrowser-tab :-moz-any(.tab-icon-sound,.tab-icon-overlay[muted]) { display: none; } I also set the about:config property called browser.tabs.showAudioPlayingIcon to False. But for some reason, the audio muted overlay is still showing up in pinned tabs. I tried to define above rule specifically for pinned tabs, but that is not working either: .tabbrowser-tab[pinned="true"] :-moz-any(.tab-icon-sound,.tab-icon-overlay[muted]) { display: none; } If anything, its even more important for the audio muted overlay to be gone from pinned tab, since, apart from aesthetics, their limited real estate makes it more likely to be clicked on accidentally. How do I remove the audio muted icon from pinned tabs? Please help!

.tabbrowser-tab[pinned="true"] :-moz-any(.tab-icon-sound,.tab-icon-overlay[muted]) { display: none !important; }