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My userChrome.css that hides the top tabs has stopped working

  • 3 replies
  • 1 has this problem
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  • Last reply by crankygoat

eriknelson
eriknelson
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I use the tree style tabs addon, so I prefer to hide the tabs along the top of the firefox window. For over a year I've used this userChrome.css file to hide them: https://github.com/eriknelson/dotfiles/blob/master/firefox/userChrome.css

Suddenly across all of my machines this has stopped working, and the tabs are still shown. I normally install it by navigating to the troubleshooting information to get my user profile location (ex: /home/ernelson/.mozilla/firefox/<profile>), creating a "chrome" directory, and copy the file there.

Has something changed with the API that would cause this sheet to be ignored? How can I troubleshoot this?

Firefox version: 72.0.1 OS: This occurs on all my systems; Windows, Arch Linux, and Fedora 31

I use the tree style tabs addon, so I prefer to hide the tabs along the top of the firefox window. For over a year I've used this userChrome.css file to hide them: https://github.com/eriknelson/dotfiles/blob/master/firefox/userChrome.css Suddenly across all of my machines this has stopped working, and the tabs are still shown. I normally install it by navigating to the troubleshooting information to get my user profile location (ex: /home/ernelson/.mozilla/firefox/<profile>), creating a "chrome" directory, and copy the file there. Has something changed with the API that would cause this sheet to be ignored? How can I troubleshoot this? Firefox version: 72.0.1 OS: This occurs on all my systems; Windows, Arch Linux, and Fedora 31

Chosen solution

At the least, you need to set a preference. Type about:config in the address bar and Enter. Find the preference toolkit.legacyUserProfileCustomizations.stylesheets and set it to "true".

There will likely be breaking changes every release or so until the rewriting of the UI chills out a bit.

This should help you if you need to adjust your userChrome.css: https://www.userchrome.org/what-is-userchrome-css.html#movetabbar

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All Replies (3)

crankygoat
crankygoat
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Chosen Solution

At the least, you need to set a preference. Type about:config in the address bar and Enter. Find the preference toolkit.legacyUserProfileCustomizations.stylesheets and set it to "true".

There will likely be breaking changes every release or so until the rewriting of the UI chills out a bit.

This should help you if you need to adjust your userChrome.css: https://www.userchrome.org/what-is-userchrome-css.html#movetabbar

eriknelson
eriknelson Question owner
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Thank you, that was the exact setting that I needed. Is this something that was recently introduced?

crankygoat
crankygoat
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Very recently, it appears, yes.