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Mouse/cursor lagging after recent FF updates

  • 9 replies
  • 1 has this problem
  • 1 view
  • Last reply by cor-el

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Hi, After recent Firefox updates (at least 3 weeks, I didn't have time too look into it) i have a serious performance issue with Firefox. When I open something i a new tab, while the page loads, my mouse lags horribly, the cursor either jumps skipping animation or just stops for a split second. It gets worse when there's a video playing in the background in a separate tab or something, it's gone when everything settles. CPU/GPU/RAM usage doesn't go past 60%/30%/30% respectively, it doesn't happen in Windows (10, 64-bit). I tried different performance settings, I tried launching Firefox in safe mode (no addons), I created a new profile, I did a fresh reinstall - nothing (more - it may've got slightly worse). I just temporarily switched to Opera and it's buttery smooth so it's definitely a Firefox issue.

Am I the only one with this issue? Any tips how to fix it? Thanks.

Hi, After recent Firefox updates (at least 3 weeks, I didn't have time too look into it) i have a serious performance issue with Firefox. When I open something i a new tab, while the page loads, my mouse lags horribly, the cursor either jumps skipping animation or just stops for a split second. It gets worse when there's a video playing in the background in a separate tab or something, it's gone when everything settles. CPU/GPU/RAM usage doesn't go past 60%/30%/30% respectively, it doesn't happen in Windows (10, 64-bit). I tried different performance settings, I tried launching Firefox in safe mode (no addons), I created a new profile, I did a fresh reinstall - nothing (more - it may've got slightly worse). I just temporarily switched to Opera and it's buttery smooth so it's definitely a Firefox issue. Am I the only one with this issue? Any tips how to fix it? Thanks.

All Replies (9)

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I also tried reverting back to FF79 - no change.

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hi, could you capture and share a performance profile while the lag is apparent? perhaps this gives more clues... https://developer.mozilla.org/en-US/docs/Mozilla/Performance/Reporting_a_Performance_Problem

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Here's a log from changing from one youtube video to another: https://share.firefox.dev/32DP6X3

It lagged like hell.

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Another one, like 3/4 of the way, mouse over the video player lagged pretty hard. https://share.firefox.dev/3hUouaw

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https://share.firefox.dev/31Mt9FU

Another one - lagged a few times there.

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thank you, from those profiles there isn't any huge obvious resource use showing either, so this is a bit of a mystery to me. perhaps you could look into if there's a new graphics driver available for your device.

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My GPU driver hasn't been updated since May (and I have issues since like early-mid August) and the updater says there is no newer one.

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Another strong lag: https://share.firefox.dev/3h0WmBn

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Boot the computer in Windows Safe mode with network support to see if that has effect in case other software is causing problems.