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Removed add-ons's data still in about:config

  • 3 replies
  • 1 has this problem
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  • Last reply by SannNord

SannNord
SannNord
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I have found several instances where Firefox add-ons that have been removed (in some cases after several release upgrades) still have the add-on setting information contained in about:config!?!

For example, the support for the NoSquint add-on has stopped. Two upgrades later I still have NoSquint entries in about:config! It seems to me that these 'artifacts' should be deleted from about:config when the add-on itself is deleted. How can I remove these about:config entries?

I have found several instances where Firefox add-ons that have been removed (in some cases after several release upgrades) still have the add-on setting information contained in about:config!?! For example, the support for the NoSquint add-on has stopped. Two upgrades later I still have NoSquint entries in about:config! It seems to me that these 'artifacts' should be deleted from about:config when the add-on itself is deleted. How can I remove these about:config entries?

Chosen solution

You can reset prefs leftover by extensions on the about:config page via the right-click context menu to the default value to have them removed on the next start.

Alternatively you can delete possible user.js and numbered prefs-##.js files and rename/remove the prefs.js file to reset all prefs to the default value including prefs set via user.js and prefs that are no longer supported in current Firefox releases.

You can use this button to go to the current Firefox profile folder:

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All Replies (3)

the-edmeister
the-edmeister
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Yep, extensions don't uninstall completely, preferences are left behind. There's no requirement that an extension remove those preferences when removed.

Best way to get rid of those unneeded preferences in about:config is to create a new Profile.

Overall, with the extension gone those old prefs are useless, the code that 'hooks' prefs is Firefox is gone and other than being clutter those prefs aren't going to affect Firefox negatively.

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Chosen Solution

You can reset prefs leftover by extensions on the about:config page via the right-click context menu to the default value to have them removed on the next start.

Alternatively you can delete possible user.js and numbered prefs-##.js files and rename/remove the prefs.js file to reset all prefs to the default value including prefs set via user.js and prefs that are no longer supported in current Firefox releases.

You can use this button to go to the current Firefox profile folder:

SannNord
SannNord Question owner
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Two reasons behind my original post:

  • to minimize the uniqueness of my Firefox browser 'fingerprint' (check out https://panopticlick.eff.org)
  • eliminating CRUFT is always a good thingbecause esidual artifacts are never helpful

Thanks for the feedback!