#stop directive no longer works

Up to xwiki 2.7, the following velocity section was working ok:

{{velocity}}
#set($user=$xwiki.getUser())
#if(!$user.isUserInGroup("XWiki.XWikiEditorsGroup"))
   {{warning}}You don't have permission to view this document{{/warning}}
   #stop
#end
{{/velocity}}

However, as of xwiki 3.0, this code breaks on an exception related to the #stop directive. It appears like the #stop syntax has changed in velocity 1.7 and affects xwiki 3.0 which moved to this new velocity engine.

I have a workaround for my own pages, but it's probably important to fix this issue since some generic pages (such as default class templates) still use the #stop directive as above and will raise an exception if that code is reached.