I believe that mod simply disallows the hot linking of the url. A user could still type the text of the url. (eg like
http://phpbb.com
instead of
http://phpbb.com).
I have an
extension in development that is waiting for 3.1.10 to be released (and the only reason for that is for
this event).
It should work on 3.1.9 even without that commit (version constraint would have to be changed in the ext.php file of the repo). It is in dev so you are warned that it hasn't been validated. Use at your own risk if you dare.
