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Firefox fills disk space to 0 bytes few times a day

  • 23 tontu
  • 3 am na jafe-jafe bii
  • 2 views
  • i mujjee tontu mooy eqall

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Hello!

I’ve been having quite strange problem with Firefox for a few months since version 80.X on clean Windows 10 (reinstalled from scratch after secure erase; the latest 20H2 version with all updates installed). It’s worth to mention that I’ve been using Firefox like 15 years and never had an issue like this before.

Firefox just fills up system drive completely (50+GB to 0 bytes remaining) few times a day under active usage. It happens randomly and I can’t identify the reason. I also can’t find any actual files saved on disk because it seems to be related to NTFS cache. I’ve tried disabling the following settings with no success:

browser.cache.disk.enable cached-web-content_cached-web-content browser.cache.memory.enable browser.cache.disk.smart_size.enabled

And couldn’t find any solution unfortunately. I usually have 2 windows opened ("common" and private) with 10 to 30 tabs each which is not much at all for i7/16GB I believe. This problem is extremely annoying and seriously affects SSD life so I'd really appreciate if someone would help me to resolve it. Thanks in advance!

Hello! I’ve been having quite strange problem with Firefox for a few months since version 80.X on clean Windows 10 (reinstalled from scratch after secure erase; the latest 20H2 version with all updates installed). It’s worth to mention that I’ve been using Firefox like 15 years and never had an issue like this before. Firefox just fills up system drive completely (50+GB to 0 bytes remaining) few times a day under active usage. It happens randomly and I can’t identify the reason. I also can’t find any actual files saved on disk because it seems to be related to NTFS cache. I’ve tried disabling the following settings with no success: browser.cache.disk.enable cached-web-content_cached-web-content browser.cache.memory.enable browser.cache.disk.smart_size.enabled And couldn’t find any solution unfortunately. I usually have 2 windows opened ("common" and private) with 10 to 30 tabs each which is not much at all for i7/16GB I believe. This problem is extremely annoying and seriously affects SSD life so I'd really appreciate if someone would help me to resolve it. Thanks in advance!

All Replies (3)

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eqall said

One more thing to mention is once some space is wasted by Firefox, there is no way to recover it by simply closing AliExpress / YouTube tabs. Things stop getting worser with these tabs closed (until re-opened) but in order to recover wasted space, Firefox should be restarted completely.

What if, after closing one or both of those tabs, you try to return unused memory to Windows by using the buttons under "Free memory" on the about:memory page? Does that make any difference?

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Just tried to reproduce an issue and it’s not easy this time for some reason. It happens quire randomly but regularly. Anyway, even if "Free memory" helps, keeping an eye on disk space all the time and constantly cleaning memory manually is uncomfortable and unreasonable to say at least. I’ve spent to much time with this with no result and just wasted a lot of SSD life in vain. That’s disappointing.

Just checked some reports and it appears that Firefox keeps losing its market share while Edge gains more every month. For a reason. Firefox has been the best browser (for me) for years but nothing is perfect and we just have to move forward, I guess.

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PS buttons under "Free memory" on the about:memory page didn’t help.

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