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Lost all Add Ons

  • 4 cavab
  • 2 have this problem
  • 5 views
  • Last reply by FredMcD

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Tried to download a new favicon add-on. Now when I click on Tools>Add-Ons> FF opens a new tab called "Add-ons Manager" and all previous add-ons/plug ins are gone. Yet Add-on bar is still ok but not complete with all add ons. Any ideas? Dan

Tried to download a new favicon add-on. Now when I click on Tools>Add-Ons> FF opens a new tab called "Add-ons Manager" and all previous add-ons/plug ins are gone. Yet Add-on bar is still ok but not complete with all add ons. Any ideas? Dan

Modified by danpbphoto

All Replies (4)

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It is possible that there is a problem with the file(s) that store the extensions registry.

Delete the extensions.* files (e.g. extensions.json, extensions.sqlite, extensions.ini) 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 "Firefox/Tools > Add-ons > Extensions" then click the Tools button at the left end of the Search bar to check if there is a compatibility update available.

If this hasn't helped then also delete the addons.json file.

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cor-el said

It is possible that there is a problem with the file(s) that store the extensions registry. Delete the extensions.* files (e.g. extensions.json, extensions.sqlite, extensions.ini) 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 "Firefox/Tools > Add-ons > Extensions" then click the Tools button at the left end of the Search bar to check if there is a compatibility update available. If this hasn't helped then also delete the addons.json file.
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When you click on Add-ons- nada, nothing zilch..opens a new tab named add-ons..I reset FF and had to manually restore all add-ons and plug ins..now ok..

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Have you tried re-installing the add-ons?

Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac Options)
key, and then starting Firefox.

Now open the Add-ons Manager. Is the problem still there?


Separate Issue; Your System Details shows;

Installed Plug-ins

Adobe PDF Plug-In For Firefox and Netscape 11.0.12 Adobe PDF Plug-In For Firefox and Netscape 15.8.20082
Having more than one version of a program may cause issues. You must remove the older programs. Then get the current full installer.


These can't get your data back, but will help in the future.

These add-ons can be a great help by backing up and restoring Firefox

FEBE (Firefox Environment Backup Extension) {web link} FEBE allows you to quickly and easily backup your Firefox extensions, history, passwords, and more. In fact, it goes beyond just backing up -- It will actually rebuild your saved files individually into installable .xpi files. It will also make backup of files that you choose.

OPIE {web link} Import/Export extension preferences