The form information that shows up in Ccleaner is in a sqlite file. Session information is in a .JS file. These are several KB in size.
Edit- Well this is total BS! I opened the session store file which is stored in a .JS file and I see all of my browsing history, yet it's suppose to clear that on exit!
I need to reencrypt my computer. I decrypted because I had a system restore issue and ran a repair install, but that didn't even fix system restore. Turns out it was Softperfect's RAM disk software interfering with system restore. I uninstalled and now I have system restore. Ever since I corrected that problem I have my laptop unencrypted. It just takes forever and I'm now due for a clone to the external. I can't believe the files I specifically tell Firefox and Pale Moon to delete on browswer close are still on my computer. I guess I'll be running Ccleaner after browser close each time. I do run a sandbox, but access is allowed to the profile so that does me no good. I need access to the profile for addon updates and saving bookmarks. Otherwise it's a PITA!