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I use Ubuntu Studio 18.04.2 LTS (64 bit Linux).
I experimented some kind of crash, due to some app which left some too big temporary file, so the home partition was full and the system couldn't start at all.
I erased some personal files, from the documents folder (unfortunately, Ubuntu put that user data folders in that partition and I don't know some way to avoid it when we install Ubuntu) and, then, I recovered some space and the system started normally, again.
But... The question is: Where is/are and What is/are that/those useless temporary files and how to full erase it?
Is there some full automatic command line to do this?
Is there some specific GUI app to do this?