According to Desktop Entry Specification:
NoDisplay means "this application exists, but don't display it in the
menus". This can be useful to e.g. associate this application with MIME
types, so that it gets launched from a file manager (or other apps),
without having a menu entry for it (there are tons of good reasons
for this, including e.g. the netscape -remote, or kfmclient openURL kind
of stuff).
Apparently over half of desktop files in default Fedora template have
NoDisplay=true...
FixesQubesOS/qubes-issues#1348
7bc6422f53