Firefox calls extensions add-ons, and they can build up quietly over time. The Add-ons Manager shows everything installed, including extensions and themes, so you can pause something temporarily, remove it for good, or check whether an add-on is causing browser trouble.
Does this affect you?
Use this for Firefox on Windows or Mac when you want to see installed add-ons, disable one without deleting it, remove one completely, or clean up a browser that has too many extensions.
Open the Add-ons Manager and see everything installed
This is the main control screen for Firefox add-ons.
- Click the three-line menu in the top-right corner.
- Choose Add-ons and themes.
- Click Extensions in the left sidebar.
- Review the list of installed add-ons and their toggle switches.
You can also type about:addons in the address bar and press Enter to open the same page directly.
Disable an add-on without removing it
Disabling is useful for testing or pausing an add-on you may want later.
- Open Add-ons and themes.
- Choose Extensions.
- Find the add-on.
- Click its toggle to turn it off.
- Restart Firefox if Firefox asks you to do so.
The add-on stops running but stays installed with its settings intact. Turn it back on from the same screen whenever needed.
Remove an add-on completely
Remove an add-on when you are sure you no longer need it.
- Open Add-ons and themes > Extensions.
- Click the three-dot menu beside the add-on.
- Choose Remove.
- Confirm the removal.
If you change your mind later, reinstall the add-on from addons.mozilla.org and set it up again.
More control
Install from trusted sources
Use addons.mozilla.org or Firefox built-in add-on search. Check ratings, user count, recent updates, and permissions before installing anything new.
Use Troubleshoot Mode
If Firefox is crashing or pages load oddly, open about:support and use Troubleshoot Mode. Firefox restarts with add-ons temporarily disabled. If the problem disappears, re-enable add-ons one at a time.
Themes live in the same manager
The Add-ons and themes page also controls Firefox themes. Themes change appearance, while extensions add behavior, but both are managed from the same place.
Sources
- Mozilla Support – Find and install add-ons to add features to Firefox (2025)
- Mozilla Support – Disable or remove Add-ons (2025)
- Mozilla Add-ons – Firefox Browser Add-ons (2025)