Those were added in 1.3 tree. What was the initial reason? We used to have a centralized cleanup function that was called on each project save. http://zerowing.idsoftware.com/viewcvs/viewcvs.cgi/GtkRadiant/radiant/gtkdlgs.cpp.diff?r1=1.18&r2=1.19&only_with_tag=MAIN