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How to edit system theme?

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  • 1 has this problem
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  • Last reply by TyDraniu

invctbehipwmohlyjq
invctbehipwmohlyjq
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Hi!

I want to edit system theme for firefox. Where exactly is it stored on the disk?

Previously it is asked here: https://support.mozilla.org/en-US/questions/940165

But that answer does not reveal the exact file location.

For example if I want to tweak font used on browser tab or shadow color around browser tab what exactly do I have to edit?

PS I dont want simply to customize colors like themes you can find on the internet do. I want to customize entire html/css that is used in FF UI.

Hi! I want to edit system theme for firefox. Where exactly is it stored on the disk? Previously it is asked here: https://support.mozilla.org/en-US/questions/940165 But that answer does not reveal the exact file location. For example if I want to tweak font used on browser tab or shadow color around browser tab what exactly do I have to edit? PS I dont want simply to customize colors like themes you can find on the internet do. I want to customize entire html/css that is used in FF UI.

All Replies (1)

TyDraniu
TyDraniu
  • Top 10 Contributor
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Everything is explained here: https://www.reddit.com/r/FirefoxCSS/comments/73dvty/tutorial_how_to_create_and_livedebug_userchromecss/