Well, looks like they finally figured it out - but it's a hacky fix, they're still not using a proper URL parser. Here are some of the ways you can trick badly implemented URL parsers (haven't tested all of them on twitter specifically, but at least a couple do indeed work):

   authority:   https://user:pass@host/[..]
   anchors:     https://[...]/path#anchor
   path params: https://host/path;param/[...]`
   port:        http://host:80/[...]`