Page property magic words like NOTOC should appear on their own line when serializing. Right now, editing a page that's already in category "Foo" and adding NOTOC as well as the category Bar produces:
[[Category:Foo]]NOTOC
[[Category:Bar]]
which shows that categories have the whitespace behavior we want (almost; they seem to get a preceding newline rather than being put on their own line, but that usually doesn't matter in practice) but magic words don't.
Version: unspecified
Severity: normal