The browser creates a %userProfile%\LocalLow\$vendor directory and temporary subdirectories

Tor Browser, Base Browser and Privacy Browser create temporary directories in %userProfile%\LocalLow\$vendor. The subdirectories are Temp-{uuid}, and the UUID seems to be always the same! So I guess it's related to the profile somehow, and different "installations" of Tor Browser produce different UUIDs.

When the browser is closed, the directory is deleted.

I don't know what it is used for.

Probably we've never noticed on Tor Browser because the vendor is Mozilla, so they should not be very distinguishable from Firefox's (if users have Firefox in their systems).

For Sponsor 131, the temporary subdirectories are deleted, but the main directory remains, even in portable mode!

Also affect Linux, but in this case /tmp/Temp-$someUUID is used, instead. And also for Linux, the UUID is persistent.