Windows 10 reached EOS (end of support) on October 14, 2025. If you are on Windows 10, see this article.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Firefox profile size has ballooned

  • 5 replies
  • 1 has this problem
  • 59 views
  • Last reply by stevenungar

I am a heavy Firefox user, and have been using it (and its predecessor) since Netscape. In the last year, the size of my Firefox profile has more than doubled, from 500MB to 1.3GB. What's the probable cause(s), and what can I do about it?

I am a heavy Firefox user, and have been using it (and its predecessor) since Netscape. In the last year, the size of my Firefox profile has more than doubled, from 500MB to 1.3GB. What's the probable cause(s), and what can I do about it?

All Replies (5)

Is the about the profile in "AppData\Roaming" used for storing your personal data or the profile in "AppData\Local" that stored temporary data like the disk cache or the sum of both locations? Did you check what files and folders take up this space? This could be about the storage folder.

The problem seems to be in the AppData\Roaming Firefox profile, in the folders archives (701MB) and default (821MB). I don't pretend to know what these folders contain. Also, I wasn't even aware that there is an AppData\Local directory. Roaming size is 2GB, while Local size is 1GB. I have never backed up Local as I didn't know it existed (should I?). BTW, thank you for your help.

In which folder do you see the archives and default folder? The /storage/default folder stores both website data (https+++) and extension data (moz-extension+++), so be careful with cleaning up this folder.

See also folders like saved-telemetry-pings and datareporting,

stevenungar said

I have never backed up Local as I didn't know it existed (should I?).

No need to back up, it just has temp files like cached pages.

Thank you, and Happy New Year!