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Upon start up Firefox (ver 84.0.2) will use 100% of my HDD for 45 to 60 minutes

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  • 1 has this problem
  • Last reply by jscher2000

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Upon start up Firefox (ver 84.0.2) will use 100% of my HDD for 45 to 60 minutes, freezing my PC for that entire time. This also happens when I start Firefox in safemode, and when I start my PC in safemode with networking. I have cleared the cache, I have deleted each extension, I have even deleted each and every bookmark. I have deleted, redownloaded, and reinstalled the latest version of Firefox. I have even done a full reinstall of Windows 10. My HDD is less than two months old, and shows no errors when scanned. This problem does occur with other browsers, but not for the same length of time, Chrome will use 100% of my HDD for one minute, tops. Once Firefox stops doing whatever it is doing to my HDD after an hour or so, it will run in the background using 0% of my Disk. Through all of this, the Memory use goes no higher than 18%, and CPU no higher than 45% for a few seconds.

If I open a second tab in Firefox, or a separate instance of Firefox, it does not use the HDD very much at all.

If I close all Firefox instances and then reopen a new one, it will, again bog down my HDD for about an hour.

The unacceptable solution I've come up with is to open Firefox immediately after turning on my PC and to leave it running in the background for that entire time.

All Replies (1)

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Firefox probably updates some files at startup, and it might finish cleanup tasks it didn't finish when it shut down, but the amount of time you're experiencing is definitely extreme.

Is this linked to system startup -- first time launching Firefox after a system startup -- or does it occur every time you exit and then restart Firefox? Based on your reference to Firefox's Safe Mode, I suspect you mean every time you exit and restart.

One method to suss out a settings issue is:

New Profile Test

This takes about 3 minutes, plus the time to test startup speed/load.

Inside Firefox, type or paste about:profiles in the address bar and press Enter/Return to load it.

Take a quick glance at the page and make a mental note of which Profile has this notation: This is the profile in use and it cannot be deleted. That is your current default profile.

Click the "Create a New Profile" button, then click Next. Assign a name like Jan2021, ignore the option to relocate the profile folder, and click the Finish button.

Firefox will switch your default profile to the new one, so click the Set as Default Profile button for your regular one to avoid an unwanted surprise at your next startup.

Scroll down to Jan2021 and click its Launch profile in new browser button.

Firefox should open a new window that looks like a brand new, uncustomized installation. (Your existing Firefox window(s) should not be affected.) Please ignore any tabs enticing you to connect to a Sync account or to activate extensions found on your system to get a clean test.

Does Firefox start up more quickly?

You can visit a couple pages to build up a little history, then close the window and then click the Launch button again to test the second start.

Similar? Different?

When you are done with the experiment, you can close the extra window without affecting your regular Firefox profile. (Jan2021 will remain available for future testing.)


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