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Windows 10 System CPU spike while using Firefox Developer Edition

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  • 1 has this problem
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  • Last reply by Shadow110

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After opening Firefox and through regular use, the System CPU on my Windows 10 Laptop will sit around 50% and climb up to 80%. No other significant processes are running (Firefox Developer Edition using the 2nd most CPU at 5-10% and 1500MB memory). Closing Firefox reverts the cpu back to 1%. Looking into the CPU usage, vsapint.sys seems to be the main culprit (aside from kernel drivers) and is significantly reduced when Firefox is closed.

Additionally, Firefox will hang and crash on close nearly every time (Not safe mode). The most recent crash report is here: bp-6c836a25-a7e0-465d-905a-b02930180109

After opening Firefox and through regular use, the System CPU on my Windows 10 Laptop will sit around 50% and climb up to 80%. No other significant processes are running (Firefox Developer Edition using the 2nd most CPU at 5-10% and 1500MB memory). Closing Firefox reverts the cpu back to 1%. Looking into the CPU usage, vsapint.sys seems to be the main culprit (aside from kernel drivers) and is significantly reduced when Firefox is closed. Additionally, Firefox will hang and crash on close nearly every time (Not safe mode). The most recent crash report is here: bp-6c836a25-a7e0-465d-905a-b02930180109

Modified by bbensch

All Replies (6)

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Was there a reason why you didn't use just standard FF?

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WestEnd said

Was there a reason why you didn't use just standard FF?

I use the development capabilities throughout my day to day work

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As you know running a Beta anything can happen. Please check the first part and if need to do the 2nd .

Please : go to the Firefox 3 Bar Menu --> Options --> Privacy & Security panel and under Permissions check (put a tick in the box) the setting to Prevent Accessibility Services from accessing your browser.

Monitor in Task Manager. Should stay below 2 gigs. If excessive then do below and monitor and change if need to...Test and go up again , go back down, it will eventually get a zone you and it can live with.

Go to the 3 Bar Menu then Options --> General --> Performance and untick everything. change the recommended size lower then see how it runs. Note: 1 = No Multiprocessor = slow again. Try 2 Restart Firefox after making these changes please.

Note : Hardware Acceleration is for Video Card, Monitor to see if remain off or to turn back on.

Please let us know if this solved your issue or if need further assistance.

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Update Video Card Drivers is a must.

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Updated the Graphics Driver that needed updating. Tried to do the other steps (Prevent Accessibility, Untick all Performance options).

Upon closing Firefox (or restarting if necessary for Accessibility) The browser hangs and crashes, and resets the boxes to their original state. Also attempted in Firefox Safe Mode but adjustments did not stick. System CPU usage is unchanged at 40-80%

bp-f65a00b1-d9e8-413a-9c92-79e910180110 bp-519d88c4-e5e2-46d5-baa2-eea1d0180110 bp-f269bc52-7717-4220-9087-9338a0180110

Modified by bbensch

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Please try : uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files and C:\Program Files(x86) Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do :

Reinstall with Current Release Firefox 57.0.4 with a Full Version Installer

Please let us know if this solved your issue or if need further assistance.