Thread:Template talk:Extension/Author/username field is broken

See https://www.mediawiki.org/w/index.php?title=Extension%3ASoundManager2Button&action=historysubmit&diff=459466&oldid=459459 -- the author had to add another string to get the authorship to show up, even though the documentation says, "If omitted then the 'username' field will be used (if present)." Please fix either the documentation or the functionality.