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Firefox is causing slow down and crashing my iMac

  • 1 reply
  • 1 has this problem
  • 17 views
  • Last reply by FredMcD

PaulLundgren
PaulLundgren
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After using Firefox for 30 minutes or longer Firefox slows and the cursor gets behind and jerky. Eventually will not respond and I have to reboot my iMac twice to clear the problems caused by Firefox. I have deleted all internet caches, cookies and web content. I have done the recommended delete and update. It works for a day or two and then the problem starts over again. Firefox is definitely causing a problem and I am going to have to stop using it. Safari does not have these problems. iMac OS 10.12.6, Firefox 59.0.2.

After using Firefox for 30 minutes or longer Firefox slows and the cursor gets behind and jerky. Eventually will not respond and I have to reboot my iMac twice to clear the problems caused by Firefox. I have deleted all internet caches, cookies and web content. I have done the recommended delete and update. It works for a day or two and then the problem starts over again. Firefox is definitely causing a problem and I am going to have to stop using it. Safari does not have these problems. iMac OS 10.12.6, Firefox 59.0.2.

All Replies (1)

FredMcD
FredMcD
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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?

Note: If you start to have any problem, Close Firefox.

https://support.mozilla.org/kb/Firefox+is+already+running+but+is+not+responding

https://support.mozilla.org/en-US/kb/firefox-slow-how-make-it-faster

https://support.mozilla.org/en-US/kb/firefox-uses-too-many-cpu-resources-how-fix

https://support.mozilla.org/en-US/kb/firefox-uses-too-much-memory-ram

https://support.mozilla.org/en-US/kb/firefox-hangs-or-not-responding