stylix firefox: update documentation

Quick update to the firefox documentation. Theming uses userChrome.css as far as I can see but the respective config entry in about:config was not enabled by default on my setup.

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Oct 08 '25 12:10 BreakingBread0

the respective config entry in about:config was not enabled by default on my setup

We do try to enable the setting automatically when it's needed:

https://github.com/nix-community/stylix/blob/09022804b2bcd217f3a41a644d26b23d30375d12/modules/firefox/each-config.nix#L59-L62

Note that this is only when Firefox GNOME Theme is selected, as in other cases we don't use userChrome.css. I believe that by default the theming for Firefox actually comes from our GTK module.

Oct 10 '25 10:10 danth

We are intentionally following Home Manager's programs.${firefox}.profiles.${profile}.extensions.force behavior

Home Manager should produce an error when force is required:

https://github.com/nix-community/home-manager/blob/c7f4214faca2f196c551b767c12a70bfa0614510/modules/programs/firefox/mkFirefoxModule.nix#L823-L830

Oct 10 '25 10:10 danth