hardcoded list of protocols for urlification is a maintenance burden and duplicate code

    @staticmethod
+ def _linkify_url_is_blacklisted(url):
+ '''Don't linkify URIs consisting of just the protocol'''
+
+ blacklist_bases = [
+ 'about',
+ 'gopher',
+ 'http',
+ 'https',
+ 'sftp',
+ 'news',
+ 'ftp',
+ 'mailto',
+ 'irc',
+ 'jabber',
+ 'apt',
+ 'data',
+ ]
+
+ for base in blacklist_bases:
+ if url in ('%s' % base, '%s:' % base, '%s://' % base):
+ return True
+ return False

from
https://code.launchpad.net/~jcsackett/launchpad/linkifier-bugs-2/+merge/43980

There's no need to manually list these, we should just use the url facilities to identify things without more than the scheme populated.