Glad to see another user with same issue in Win 7. Upload images going black and white. Let me boot to Win7 and look at my temp.

I do see the folders, but there is no size issue. see screenshot

I realise there is not really a size issue although over the course of time these build up. The point is that they don't autodelete on my Windows 7 although I presume they are doing on Windows 10 because I don't see them there. I don't want to have to keep manually deleting from my temp folder. I know this issue relates to "Enable background updates" as described in https://support.mozilla.org/en-US/kb/enable-background-updates-firefox-windows I had recently unchecked "When Firefox is not running" so it didn't keep looking when the computer was off but I've now turned it back on because that meant they were not actually doing the updates even though I have "Use background service to install updates" checked. (In order to do the last update when this was turned off, I had to troubleshoot). So now I'm back to having one of the background task files every 7 hours day & night. Should I change to "Check for Updates but let you choose when to install them"? This might mean I still get these folders proliferating. The problems seem to lie with the fact that the folders do not auto-delete from the C:\Users\<username>\AppData\Local\Temp folder in Windows 7 (whereas in Windows 10 it seems to work differently & doesn't leave these folders behind)