Thread:Feedback/Templates in sigs

Signatures including "pipe" characters that work on established wikis, are breaking under LT.

For example a signature containing Special:Emailuser/ExampleEmail me works on enwiki but displays as raw markup on LT. (The "subst:!" is needed to allow piped links in a user's sig, without breaking other templates, which often happens when a user signs with /~ as part of a message within many templates.)