I also noticed that youtube videos are not getting automatically embeded and usernames mentions are not working.
I set up a form with 2 single line text fields:
One has to be manually filled with a username (example, they type "Snog") and in the form settings, I specified that the answer will have the "@" symbol before, so once they post it, it becomes:
@Snog and it works, but the mention isn't parsed as url and is left as blank text, so there is no real mention.
The other has to be filled with a youtube video url. Normally, when you place a youtube url on xenforo (without any bbcodes), it gets automatically converted to a media embeded youtube video, while this doesn't seem to happen using Snog Forms.
I also had another issue with a field which had to be filled with a forum link, which, once posted wasn't automatically parsed as url, but I fixed it on the backend by setting the url bbcode in the answer box, similarly to the mention @ symbol.
I would also like to specify that all this doesn't seem to happen with all the users, but only with some of them.
Hope it helps somehow. Thank you.
EDIT
I just noticed "Parse URL" wasn't checked, so I just enabled it, altough I'm not sure if it's gonna solve the youtube and mention issues. Thanks.