Wikimedia Bugzilla is closed!

Sometimes, when copying and pasting page titles from the interface (it's been
reported on [[WP:VPT]] that it happens when copying a page title from your
watchlist), a page title gets an extra LRM at the beginning or the end. This
causes pages or links to pages to be created with titles starting or ending with
an invisible unprintable character, which is confusing (causing, for instance,
unexpected redlinks or duplicate articles).

To avoid it, that character should be disallowed on page titles, together with
similar ones; also, to reduce newbie confusion, instead of throwing an error
message when these characters are found on a page title, they should be silently
stripped.