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Browser theme disappearing after start

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  • 1 has this problem
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  • Last reply by cor-el

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After enabling any theme when I close and reopen Firefox it's theme disappearing. Version: 100.0.2(64 bit).

After enabling any theme when I close and reopen Firefox it's theme disappearing. Version: 100.0.2(64 bit).

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Is this with a custom theme from the Add-ons website or also with a built-in (colorways) theme ?

You can check for problems with preferences. You can delete possible user.js and numbered prefs-##.js files and rename/remove the prefs.js file to reset all prefs to the default value including prefs set via user.js and prefs that are no longer supported in current Firefox releases.

You can use the button on the "Help -> More Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page (Root directory).