As user "richard" I created 3 files. I later wanted to protect them totally from accidental change.For each file, I went to Properties->Permissions and changed Access for Owner, Group, and Others to "Read Only".
As user "richard" I was able to delete them with Caja. *UNDESIRABLE*As "root" I changed Owner and Group to "root" leaving Access for all as "Read Only".
User "richard" could still *DELETE THEM*! "Read Only" evidently does not mean what it implies. What's happening? TIA