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On Mojave, Firefox will often stop responding after I come back and unlock my Mac. How can I fix this?

  • 8 replies
  • 2 have this problem
  • Last reply by aaron.cline

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This one is hard to pin down, but occasionally Firefox will go unresponsive but will accept one previous mouse action (like clicking a tab) when I put Firefox in the background by clicking another open non-Firefox window and bringing it to the front.

How this happens:

1. I lock my macbook and step away from the desk for an undetermined amount of time. 2. I come back to my desk and unlock my computer. 3. I click on firefox to browse for something and it doesn't respond 4. I'll click another tab that isn't in focus, nothing will happen 5. I click on any other open application and I will notice that Firefox will change to the tab I had just clicked on 6. If I go back to Firefox, it will not respond to anything until I bring some other application to focus.

Sometimes, if I wait a long time like 10 or 15 minutes, the problem will resolve itself. Usually I just get frustrated and close Firefox.

I feel like this has to be a problem between Firefox and some other application that I run. Some other appications that are typically open are:

iTerm2 Spotify Lastpass Plugin Microsoft Outlook Sometimes TweetDeck Maybe another Firefox profile

I have been unable to regularly reproduce this issue, but it will typically happen multiple times a day.

One other behavior that I have noticed is that I can click the address bar and nothing visible happens, but if I start typing, the suggestion bar will pop up and accept the text I am typing. I am including a picture of that behavior

All Replies (8)

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

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?

Start your Computer in safe mode with network support. Then start Firefox. Try Secure websites. Is the problem still there? Starting Any Computer In Safe Mode; Free Online Encyclopedia

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I started Firefox in safe mode and the problem still exhibited itself.

I think this is a bug, is there a way to enable some debug logging?



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Did you try the Computer in Safe Mode?

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No, its pretty hard to work in OS Safe Mode. What are my other options?

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I did not want you to work. Just use the computer and see if the problem is still there.

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This is, unfortunately, still a recurring issue for me. I can not make the problem happen and I don't have time to sit in Safe Mode and try to make it happen. Are there other debugging steps I could try? Is there a flag I can pass to Firefox at startup that might reveal some debugging information I could utilize?

I'm currently on Mojave 10.14.1

Thank you for your help.

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I called for more help. You should also post your question on a Mac support forum.

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Will do. Thanks you.