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Since updating Firefox it won’t open. MacBook says application not responding!

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So now Firefox won’t open on my old MacBook Pro - it freezes entire laptop and says application not responding - then forcing app to quit takes about 3 mins but unless I do that I can’t use laptop. Whilst it’s running (but not opening) I can’t even go into the toolbar to try to update Firefox settings etc as laptop is frozen until I force the app to quit. I have tried rebooting. - dropping app into trash and reinstalling but nothing works - any ideas??

So now Firefox won’t open on my old MacBook Pro - it freezes entire laptop and says application not responding - then forcing app to quit takes about 3 mins but unless I do that I can’t use laptop. Whilst it’s running (but not opening) I can’t even go into the toolbar to try to update Firefox settings etc as laptop is frozen until I force the app to quit. I have tried rebooting. - dropping app into trash and reinstalling but nothing works - any ideas??

All Replies (5)

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Sorry to hear about this problem. If you haven't solved this arleady:

Since you already replaced the Firefox.app, you could try creating a new profile to see whether Firefox can start up that way. It won't have any of your settings, but if the new profile works, we could suggest some selective file restorations.

This article describes how to use the Terminal to start up the Profile Manager to create a new profile. Please do not delete any existing profiles in the process.

Profile Manager - Create, remove or switch Firefox profiles

Skip to the "Start the Profile Manager when Firefox is closed" section of the article.

Can you get Firefox to run in a new profile?

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Thank you so much - that bit has worked so now what do I do - delete the "default" user but retain files or is there any other way of transferring all my bookmarks from old account to new one I have just created please?

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Also why is the time wrong on this message? I posted this at 18.18 not 10.18?

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Hi LUCYRS, If you have Firefox Sync set up, you can sign in to your account, and all of your synced data will be imported.

If you don't have Firefox Sync set up, follow the instructions in the following article: Recover important data from an old profile

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LUCYRS said

Thank you so much - that bit has worked so now what do I do - delete the "default" user but retain files or is there any other way of transferring all my bookmarks from old account to new one I have just created please?

If you didn't already have Firefox Sync set up, here's how to restore a bookmark backup from your old profile to your new one:

(A) Open the about:profiles page (type or paste that in the address bar and press Return to load it)

(B) Open the "Root" folders for both your old and new profiles in Finder

You can use the "Show in Finder" buttons under the respective profiles.

(C) Copy one or two of the most recent files from the bookmarkbackups folder in the old profile to the corresponding folder in the new profile

You can close the two Finder windows after that

(D) The transplanted backup should now appear on the Restore menu in the running Firefox. See:

Restore bookmarks from backup or move them to another computer