Comment 4 for bug 234661

Clearing the cache at shutdown doesn't work. Or not in itself.
For example, the cookperm.txt is written when there are changes. This means that
it isn't written at shutdown. So, if the last attempt to wirte failed due to no
disk space, and then at shutdown there suddenly is disk space, the file is still
not written to disk.
Afaik, the same goes for cookies. I don't know about others.