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On startup, all my add-ons are deactivated, and a few empty tabs are open.

  • 5 replies
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  • Last reply by cor-el

SThor
SThor
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As said in the title, every time I open Firefox, all my add-ons are deactivated, although they don't show as such in the add-ons tab. In order to have them working again, I have to deactivate and reactivate them.

On top of this, a few empty tabs show up. I use the "restore all my last session's tab on startup" setting, so these just appear after all the normal ones. A few of them show up with an address like this : " open.data:application/vnd.mozilla.xul+xml;charset=utf-8,<window/> ", while the other show up with the address of the pinned tabs I have, only incomplete, with just root address ( I mean like this : "support.mozilla.org" instead of that : "https://support.mozilla.org/en-US/questions/new/desktop/fix-problems/form?search=On+startup%2C+all+ [...]" ). There is no webpage loaded in any of those tabs, but it doesn't say "New Tab" either, just an empty tab. When I click anywhere, "New tab" appears on all the previously empty tabs.

Here are a couple screenshots to illustrate all of that : before clicking : http://puu.sh/gAs1S/7ed9e1ac3f.jpg and after : http://puu.sh/gAs2j/cfb622c945.jpg

As said in the title, every time I open Firefox, all my add-ons are deactivated, although they don't show as such in the add-ons tab. In order to have them working again, I have to deactivate and reactivate them. On top of this, a few empty tabs show up. I use the "restore all my last session's tab on startup" setting, so these just appear after all the normal ones. A few of them show up with an address like this : " open.data:application/vnd.mozilla.xul+xml;charset=utf-8,<window/> ", while the other show up with the address of the pinned tabs I have, only incomplete, with just root address ( I mean like this : "support.mozilla.org" instead of that : "https://support.mozilla.org/en-US/questions/new/desktop/fix-problems/form?search=On+startup%2C+all+ [...]" ). There is no webpage loaded in any of those tabs, but it doesn't say "New Tab" either, just an empty tab. When I click anywhere, "New tab" appears on all the previously empty tabs. Here are a couple screenshots to illustrate all of that : before clicking : http://puu.sh/gAs1S/7ed9e1ac3f.jpg and after : http://puu.sh/gAs2j/cfb622c945.jpg

Chosen solution

FredMcD said

Delete a possible user.js file and numbered prefs-##.js files and rename (or delete) the prefs.js file to reset all prefs to the default http://kb.mozillazine.org/Preferences_not_saved

It looks like this fixed it. Unfortunately, at the same time it lost all of the open tabs and tabs groups I had. :(

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All Replies (5)

FredMcD
FredMcD
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Delete a possible user.js file and numbered prefs-##.js files and rename (or delete) the prefs.js file to reset all prefs to the default http://kb.mozillazine.org/Preferences_not_saved

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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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.

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

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 possible addons.json and addons.sqlite files.

SThor
SThor Question owner
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Chosen Solution

FredMcD said

Delete a possible user.js file and numbered prefs-##.js files and rename (or delete) the prefs.js file to reset all prefs to the default http://kb.mozillazine.org/Preferences_not_saved

It looks like this fixed it. Unfortunately, at the same time it lost all of the open tabs and tabs groups I had. :(

SThor
SThor Question owner
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SThor said

Unfortunately, at the same time it lost all of the open tabs and tabs groups I had. :(

I managed to get back most of my tabs by using a few weeks old backup that I had.

cor-el
cor-el
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  • Top 10 Contributor
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Tabs and Tab groups are in the sessionstore.js file, so modifications to prefs.js shouldn't effect that.