When the user clicks Reply on a message that already has an indented tangent, the new message appears directly below the existing tangent. This implies that the new message is a response to the tangent, instead of a reply to the original post.
What we should do:
* Add < @[[User:Username]] > in the entry field when the user clicks Reply on a message that already has an indented tangent. The mention can be deleted if the user doesn't want to include it.