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Firefox is extremely slow until I restart with offline Windows Defender scan

  • 4 ردود
  • 1 has this problem
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  • آخر ردّ كتبه Lorakahn

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Firefox has been extremely laggy and slow lately. I've tried every "quick fix" I've found online, to include refreshing, sfc /scannow, disabling extensions, re-installing firefox, running malware scans, etc. This started after a cluster of windows, firefox, NVIDIA updates about a week ago, and I haven't been able to pinpoint the source of the issue. So far the only thing that brings the browser back to full speed is restarting my computer with an offline Windows Defender scan. It never actually finds anything, but when the computer restarts Firefox works at regular speed until it is locked for a couple hours or restarted. Any thoughts?

Firefox has been extremely laggy and slow lately. I've tried every "quick fix" I've found online, to include refreshing, sfc /scannow, disabling extensions, re-installing firefox, running malware scans, etc. This started after a cluster of windows, firefox, NVIDIA updates about a week ago, and I haven't been able to pinpoint the source of the issue. So far the only thing that brings the browser back to full speed is restarting my computer with an offline Windows Defender scan. It never actually finds anything, but when the computer restarts Firefox works at regular speed until it is locked for a couple hours or restarted. Any thoughts?

الحل المُختار

thanks for following up. the behaviour you're seeing may be the same as https://bugzilla.mozilla.org/show_bug.cgi?id=1575216 which just received a patch on firefox 70 beta. could you try if the problem is still reproducible there?: https://www.mozilla.org/firefox/beta/all/

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hi, would you be able to capture and share a performance profile over 15-30 seconds while the lag is occurring? https://developer.mozilla.org/en-US/docs/Mozilla/Performance/Reporting_a_Performance_Problem

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First link is just scrolling up and down on the Gecko instructions page. Page lagged out during scrolling.

https://perfht.ml/2LJ6KBs

Second link is searching a word on google and scrolling the results, then clicking on two of the links. Same results, delayed response. Also had delayed response just clicking on the gecko button, similar to lag when trying to open Firefox settings or bookmarks menu.

https://perfht.ml/2LG2lPG

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الحل المُختار

thanks for following up. the behaviour you're seeing may be the same as https://bugzilla.mozilla.org/show_bug.cgi?id=1575216 which just received a patch on firefox 70 beta. could you try if the problem is still reproducible there?: https://www.mozilla.org/firefox/beta/all/

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That seems to have solved it. Sorry for the delay, I wanted to give it some time and a few power cycles to see if it held. I haven't been able to reproduce the issue after installing the beta patch. Thanks!