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CPU usage too high while using Firefox

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  • 1 has this problem
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  • Last reply by FredMcD

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I was trying to use Firefox in at least 20 minutes or so, but then something went wrong. The CPU usage was going high to 90% to 100% after usage. I'm using the dual core processor (Intel Pentium Dual Core @2.00 GHz) and my PC was super slow. And I'm too scared what's going to happen, so I immediately restart my computer and everything was back to normal without opening Firefox. It happened last night (yesterday at 9:00 PM Greenwich Mean Time +6:30) Is this an issue or is that a bug? I wanted to get this fixed. Thank you!

Best regards, Wai Min Soe

I was trying to use Firefox in at least 20 minutes or so, but then something went wrong. The '''CPU usage was going high to 90% to 100%''' after usage. I'm using the dual core processor (Intel Pentium Dual Core @2.00 GHz) and my PC was super slow. And I'm too scared what's going to happen, so I immediately restart my computer and everything was back to normal without opening Firefox. It happened last night (yesterday at 9:00 PM Greenwich Mean Time +6:30) Is this an issue or is that a bug? I wanted to get this fixed. Thank you! Best regards, Wai Min Soe
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More than one process is normal for the current Firefox. http://www.ghacks.net/2016/07/22/multi-process-firefox/

Multi-process Firefox is codenamed "e10s". https://wiki.mozilla.org/Firefox/multiprocess


Start Firefox using Troubleshoot(Safe) Mode {web link}

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


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