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System get heated when using firefox

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  • Last reply by Scribe

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While using Firefox, my system starts heating much. I checked its CPU usage and found it is using more than 25% and a lot of RAM it is using. Often this happens and Firefox is not responding at that time or responding very slowly.

Please help me to troubleshoot this problem.

While using Firefox, my system starts heating much. I checked its CPU usage and found it is using more than 25% and a lot of RAM it is using. Often this happens and Firefox is not responding at that time or responding very slowly. Please help me to troubleshoot this problem.
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Hi, first try Safe Mode to see if the problem goes away. Firefox Safe Mode is a troubleshooting mode that temporarily turns off hardware acceleration, resets some settings, and disables add-ons (extensions and themes).

If Firefox is open, you can restart in Firefox Safe Mode from the Help menu:

  • Click the menu button New Fx Menu, click Help Help-29 and select Restart with Add-ons Disabled.

If Firefox is not running, you can start Firefox in Safe Mode as follows:

  • On Windows: Hold the Shift key when you open the Firefox desktop or Start menu shortcut.
  • On Mac: Hold the option key while starting Firefox.
  • On Linux: Quit Firefox, go to your Terminal and run firefox -safe-mode
    (you may need to specify the Firefox installation path e.g. /usr/lib/firefox)

When the Firefox Safe Mode window appears, select "Start in Safe Mode".

SafeMode-Fx35

If the issue is not present in Firefox Safe Mode, your problem is probably caused by an extension, theme, or hardware acceleration. Please follow the steps in the Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems article to find the cause.

To exit Firefox Safe Mode, just close Firefox and wait a few seconds before opening Firefox for normal use again.


Also see Firefox uses too much memory or CPU resources - How to fix

And Firefox uses too much memory or CPU resources - How to fix

If your question is resolved by this or another answer, please take a minute to let us know. Thank you!