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Cannot add new search addons -- error says I'm not running Firefox

  • 3 replies
  • 1 has this problem
  • 3 views
  • Last reply by cor-el

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I'm running Firefox 39.0, and trying to install the [WorldCat search plugin](https://addons.mozilla.org/en-US/firefox/addon/worldcat/?src=search). I can't -- I get an error,

   Sorry, you need a Mozilla-based browser (such as Firefox) to install a search plugin.

It looks like another user encountered the same error: https://support.mozilla.org/en-US/questions/1062916 but their solution won't work in this case.

I'm running Firefox 39.0, and trying to install the [WorldCat search plugin](https://addons.mozilla.org/en-US/firefox/addon/worldcat/?src=search). I can't -- I get an error, Sorry, you need a Mozilla-based browser (such as Firefox) to install a search plugin. It looks like another user encountered the same error: https://support.mozilla.org/en-US/questions/1062916 but their solution won't work in this case.

Chosen solution

Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

  • Switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance
  • Do NOT click the Reset button on the Safe Mode start window
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All Replies (3)

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Chosen Solution

Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

  • Switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance
  • Do NOT click the Reset button on the Safe Mode start window
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Safe Mode worked. But it is still kind of a bogus error.

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I think that it is caused by one of the extensions that Ubuntu adds to Firefox.

  • Ubuntu Firefox Modifications
  • Unity Websites integration