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FF4 compatible addons keep disabling as they're 'not compatible with FF4'.

  • 3 replies
  • 9 have this problem
  • 15 views
  • Last reply by whoisus

whoisus
whoisus
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FF4 compatible addons (like adblock plus and downloadhelper) keep disabling and saying they're not compatible with FF4. I then have to reinstall the addon (often the very same version as before), it works again for a random number of days before deciding it's incompatible again. Is there any way to fix this?

FF4 compatible addons (like adblock plus and downloadhelper) keep disabling and saying they're not compatible with FF4. I then have to reinstall the addon (often the very same version as before), it works again for a random number of days before deciding it's incompatible again. Is there any way to fix this?

All Replies (3)

TonyE
TonyE
  • Moderator
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This can be caused if one of the files that stores details of installed extensions is corrupt.

  1. Open your profile folder, for details of how to find it see https://support.mozilla.com/kb/Profiles
  2. Close Firefox
  3. Delete the following files if they exist, extensions.cache, extensions.rdf, extensions.ini and extensions.sqlite
  4. Re-start Firefox, it will then rebuild the list on installed extensions
cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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You may also need to reset the preferences.

whoisus
whoisus Question owner
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That's fixed the problem. Thank you!