Firefox Community Forum

Dear Mozilla Support Team,

I am writing to report an issue I have consistently encountered while using the Firefox browser. Whenever I log into my Mozilla account, the custom theme I have selected for Firefox is reset to the default theme. This necessitates manually re-selecting my preferred theme each time I log in.

This issue is a minor inconvenience, but it disrupts my user experience. I would appreciate it if you could investigate this behavior. I am using the latest version of Firefox on Windows 11 Pro.

Thank you for your time and attention to this matter. I look forward to a resolution.

Sincerely,

Clóvis Lauriano laurianoperez@yahoo.com.br

I’m at my wits’ end with this. Firefox keeps forcing a system-synced theme at launch, and it flat-out refuses to respect the settings I’ve configured — both in about:config and via a custom user.js file.

Here’s what I’ve tried:

• Set layout.css.prefers-color-scheme.content-override to 0 in about:config → it reverts back to 2 after every restart.

• Created a user.js with user_pref("layout.css.prefers-color-scheme.content-override", 0); → completely ignored.

• Disabled all sync options, including themes.

• Verified that no active studies are interfering.

• Double-checked that I’m not syncing across devices.

• Tried applying a specific theme and setting it manually — still overridden at launch.

No matter what I do, Firefox insists on syncing the theme to the system’s dark/light setting. I want my browser theme independent from the OS — period.

Is there a deeper setting I’m missing? A hidden override? Some service that’s reapplying the system setting post-launch? This feels like Firefox is actively fighting me — and it's infuriating.

Would appreciate any insight or workaround. I just want full manual control over my theme. Why is that so hard?

Hi there,

I'm experiencing a theming issue when using Firefox (flatpak) on Hyprland with a pure black (#000000) theme applied via a theme extension. When the Firefox window is out of focus, everything looks fine — the background is truly black as expected. However, when the focus is on the window, the blacks turn washed out grey, losing the #000000 appearance. This doesn't seem to happen in other apps and I don't seem to have any filter for the focused windows (except for borders), so it seems related to how focused windows are handled in Hyprland or how Firefox draws its content under Wayland - have you heard about this issue and could you help me diagnose it + find a solution? Is there a setting I could tweak either in Hyprland, Firefox, or GTK/Qt config to prevent this color shift on focus? Thanks in advance!

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I am unable to remove add on themes. The remove button is not provided. Only manage which enables the theme. I do not want these themes and want them removed now. mac ios

you are repeating old mistakes. You have become worse than Microsoft. Firefox is not remembering open tabs again. I have supported your Firefox until now but enough is enough.

I have literally over 200 tabs open at a time and recover them every time I reboot Firefox, but they are very disorganized. Is there a good way to organize them, for example, group related tabs together?

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Good Day,

I am leaving Brave as my default browser for Firefox.... Brave is good, just would prefer Firefox. I used to love it.

The problem is...I have a theme on Brave and Chrome that I love dearly. Is there a way to bring that theme to Firefox? I tried using Firefox Color, but it looked awful.

PS: I am the tech Village Idiot so please talk to me in that vein ;)

Thank you and Warmest Regards, Alisa (Stormwolfe)

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