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Firefox using 50%+ of the CPU when it is inactive & only stops when I close & reopen it; then it starts it again after it is loaded for a while.

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  • 88 have this problem
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  • Last reply by Borne

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With Firefox loaded but sitting inactive for a period, it starts to use 50%+ of the CPU (per Windows Task Manager). This slows down everything even though there is nothing (overtly) going on with Firefox. If I close & reopen it, it is OK for a while, and then it starts again.

== In the past week, but I know of no specific event out of the usage ordinary.

With Firefox loaded but sitting inactive for a period, it starts to use 50%+ of the CPU (per Windows Task Manager). This slows down everything even though there is nothing (overtly) going on with Firefox. If I close & reopen it, it is OK for a while, and then it starts again. == In the past week, but I know of no specific event out of the usage ordinary.

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Chosen Solution

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I found the reason being the company web filter blocking one of my plugins. To test it you look for a plugin that is not working right and uninstalling it.

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Thank you for the link "AnonymousUser"... but the link no longer works.

I have been having this same issue for months now. It seems like at random times FF just jumps up to 50% CPU usage and basically freezes (very slow), and I have to restart it.

Sometimes when restarting FF it still does it, so I have to restart again.