In posting.php:1009, the message body is only parsed if the message is updated. However, in the textformatter/s9e/utils.php, the function get_outermost_quote_authors relies on the text being parsed. So, whenever is a post is edited and submitted with no changes or only the subject edited, the quote authors can never be found. One side-effect of this is the deletion of any notifications for the quote in the post that was edited.