File history can be disabled in Gnome3 and things no longer show up in that menu.
I'm on someone else's system at the moment. They use Xfce (me too) not Gnome, and it is a mixed GTK2 and GTK3 system.
I have a note that I followed this advice on my own laptop, but I can't quite remember now.
I'll either have to put up with this annoyance or spend an hour or two trying to fix it. Grrr!
It's a PITA all right, that these systems are in use by multiple projects but not all the levers and dials are exposed to everyone.
Though... this is a bit cursed, but I wonder if you can install Gnome's control panel separately from Gnome itself, just to tweak all the appropriate GTK knobs? :P
'course Xfce might be using an older/forked GTK, so I dunno if that even makes sense..
From memory the Gnome panel only sets GTK3 stuff, might be wrong.
I never use the "Recently Used" files as I structure things and put them in hierarchical folders. I don't mind RU as an option, but file choosers DEFAULT to this virtaul folder. I then have to click all the way down to my PWD again.
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