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userChrome.css and Firefox Developer Edition

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  • Last reply by MiltS
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MiltS
MiltS

Firefox Developer 80.0b7 (64-bit) Mac Catalina V 10.15.5

I've tried using the userChrome.css file to change the background color for the active tab. create chrome folder in profile folder create userChrome.css file and add: .tab-background[selected="true"] { 

 background-color: #ffffff !important;
 background-image: none !important;

} Set toolkit.legacyUserProfileCustomizations.stylesheets to TRUE Reboot mac This does not take affect and the userChrome.css file is not visible in Style Editor.

What am I doing wrong? thanks Milton

Firefox Developer 80.0b7 (64-bit) Mac Catalina V 10.15.5 I've tried using the userChrome.css file to change the background color for the active tab. create chrome folder in profile folder create userChrome.css file and add: .tab-background[selected="true"] { background-color: #ffffff !important; background-image: none !important; } Set toolkit.legacyUserProfileCustomizations.stylesheets to TRUE Reboot mac This does not take affect and the userChrome.css file is not visible in Style Editor. What am I doing wrong? thanks Milton

All Replies (2)

cor-el
cor-el
  • Top 25 Contributor
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You can open the userChrome.css file in a Firefox tab to check if the file is a plain text file and not a file with RTF or other formatting code.

MiltS
MiltS Question owner

Yes it opens in a tab. It is a text file.