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Documentation/Command reference
COMMAND REFERENCE

fxcss profiles

fxcss 0.22.1Source documentation
bash
fxcss profiles                       # what is themed where
fxcss profiles --check               # …and whether anything newer exists
fxcss profiles --json                # machine-readable

Read-only. Firefox keeps its profiles in directories named after a hash, so it can be hard to tell which profile has the theme by looking at folder names:

console
$ fxcss profiles --check

  Firefox profiles on this machine

  ● default-release          [Release]
    ~/Library/Application Support/Firefox/Profiles/8f2h1kqp.default-release
    theme    AdamXweb/WhiteSurFirefoxThemeMacOS @ v1.0.0
             installed 2026-08-14 09:12:44  (tracking the release)
    sheets   theme-nord
    files    137 file(s), 1 edited since install, 1 added by hand
    update   v2.0.0 available  — 2026-08-16

    dev-edition-default      [Developer Edition]
    ~/Library/Application Support/Firefox/Profiles/p93kd0zx.dev-edition-default
    chrome/  41 file(s), not installed by fxcss
             `fxcss install` here would back this up first

  ● the profile Firefox opens by default

Three states, kept distinct on purpose: a profile fxcss installed into and can speak for, a profile with a chrome/ folder someone put there by hand, and a profile with no theme at all. Only the first can be described in detail; for the second, all fxcss honestly knows is that files are there and that installing would move them aside.

--check asks GitHub once per theme, not once per profile, and compares like for like: an install tracking releases is measured against the newest tag, one tracking a branch against the commit that branch points at now. An install pinned with --ref reports as pinned rather than as behind. Where the manifest predates fxcss recording which of those applied, it says so instead of guessing — "up to date" is never printed unless it was actually checked.

The same reservation covers local edits: installs from before 0.16 recorded no file hashes, so fxcss profiles reports them as not checked for edits rather than as unmodified. Reinstalling records them.

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