Uninstall Firefox on Mac
Back up your Firefox profile before quitting and removing the app. Bookmarks, passwords, and extensions live in the profile under ~/Library/Application Support/Firefox/Profiles, not in the caches below, and removing the app does not delete them. These steps cover Firefox downloaded from Mozilla and the Homebrew cask firefox. Mozilla’s uninstall instructions
Find and back up the profile
Open about:support in the address bar and use the button beside Profile Folder to open it in Finder. Then quit Firefox and copy the entire profile folder to a backup location. Do not copy changing databases while Firefox is running. Firefox’s backup instructions
Keep the profile if you only want to remove the browser. If you want a reset, verify your backup before deciding to delete the profile. After Firefox is moved from Applications to the Trash, a retained profile does not run by itself.
If you installed it with Homebrew
The firefox cask’s zap list includes ~/Library/Application Support/Firefox, which holds every Firefox profile, along with its caches and preferences. Running brew uninstall --cask --zap firefox yourself deletes your bookmarks, passwords and extensions stored on this Mac. Mole never adds --zap for a browser cask; it runs the plain command, which removes the app and leaves the profile:
brew uninstall --cask firefox
Where Firefox keeps its data
| Location | What it holds | What to do |
|---|---|---|
~/Library/Application Support/Firefox/Profiles |
Your profiles: bookmarks, passwords, history, extensions | Back up; keep unless you want a full reset |
~/Library/Caches/Firefox |
Firefox’s disk cache | Safe to remove after Firefox has quit |
~/Library/Caches/Mozilla/updates/Applications/Firefox |
Downloaded Firefox updates | Safe to remove |
~/Library/Caches/org.mozilla.firefox |
App cache | Safe to remove |
Leave ~/Library/Caches/Mozilla and ~/Library/Application Support/Mozilla themselves in place. Other Mozilla apps such as Thunderbird, and native-messaging hosts of other programs, share those parents. If you only want disk space back, see Free Up Chrome and Safari Storage on Mac Safely.
Check the result
Run these read-only commands after the app is in the Trash:
pgrep -il firefox
ls "$HOME/Library/Application Support/Firefox/Profiles"
- No output from
pgrepmeans Firefox has quit. A listed process means a copy is still running; quit it before copying or deleting profile data. lslisting folders means your profiles are still on this Mac, which is expected unless you chose a full reset. “No such file or directory” means they are gone.
A Firefox profile is not an update cache
After backing up, inspect the copied profile for bookmarks, password data, and extension settings before considering removal of the original. The updates/Applications/Firefox entry is an update-download location. Clearing it neither resets the profile nor verifies that your profile backup is usable.
If a Mozilla parent folder remains after uninstalling, check for other Mozilla software such as Thunderbird. Do not empty the whole parent directory just because it contains a Firefox subdirectory.
What Mole lists
When you remove it with Mole:
~/Library/Application Support/Firefoxis shown as shared browser data and kept. Firefox editions share that folder, so Mole does not offer it for deletion; remove a profile yourself from Firefox or Finder after backing it up.~/Library/Caches/Mozilla/updates/Applications/Firefox,~/Library/Caches/Firefox, and the caches, preferences and saved window state filed underorg.mozilla.firefoxare selected by default.~/Library/Caches/Mozillaand~/Library/Application Support/Mozillaare not listed.
What this test covered
Firefox was installed from the Homebrew cask firefox and uninstalled with Mole on September 17, 2026. That run added the exact updates/Applications/Firefox cache row to Mole, as a rule that also covers other Firefox-based browsers. A recheck on September 26, 2026 used Firefox 156.0.1 downloaded from Mozilla and a development build of Mole: Status showed Firefox as one row of 14 processes, about 920 MB, the app and its five selectable rows went to the Trash, and ~/Library/Application Support/Firefox stayed as shared browser data. Profile backup and restore were not tested.