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Why did almost all of my add-ons disappear suddenly?

  • 1 reply
  • 2 have this problem
  • 1 view
  • Last reply by cor-el

jbacinti
jbacinti
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FF 46.0.1 user here and not real happy. I went to Tools / Addons to see why my Tabs were back on top. When there all but 2 of my addons were noted as needing a restart. I thought that to be strange but went ahead and restarted FF. All those addons disappeared. What happened and where, if at all, can I find a list of the addons I was using?

FF 46.0.1 user here and not real happy. I went to Tools / Addons to see why my Tabs were back on top. When there all but 2 of my addons were noted as needing a restart. I thought that to be strange but went ahead and restarted FF. All those addons disappeared. What happened and where, if at all, can I find a list of the addons I was using?

Chosen solution

You can check the extensions folder in the Firefox profile folder to see if the extensions files are still there. You can use this button to go to the current Firefox profile folder:

It is possible that there is a problem with files in the profile folder that store the extensions registry.

Delete the extensions.* files (e.g. extensions.json, extensions.ini, extensions.sqlite) and compatibility.ini in the Firefox profile folder to reset the extensions registry.

New files will be created when required.

See "Corrupt extension files":

If you see disabled or not compatible extensions in ""3-bar" menu button or Tools > Add-ons > Extensions" then check if there is a compatibility update available.

  • click the cogwheel button (left of the Search bar) on the about:addons page to "Check for Updates"

If this didn't help then delete add-ons.json and possibly prefs.js in case there is a problem with preferences.

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All Replies (1)

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

You can check the extensions folder in the Firefox profile folder to see if the extensions files are still there. You can use this button to go to the current Firefox profile folder:

It is possible that there is a problem with files in the profile folder that store the extensions registry.

Delete the extensions.* files (e.g. extensions.json, extensions.ini, extensions.sqlite) and compatibility.ini in the Firefox profile folder to reset the extensions registry.

New files will be created when required.

See "Corrupt extension files":

If you see disabled or not compatible extensions in ""3-bar" menu button or Tools > Add-ons > Extensions" then check if there is a compatibility update available.

  • click the cogwheel button (left of the Search bar) on the about:addons page to "Check for Updates"

If this didn't help then delete add-ons.json and possibly prefs.js in case there is a problem with preferences.