smilie error

I want to add edit existing smilies, but if I edit one, then I either get the error: Please enter a valid emoji short-name or image URL. Yet, the smiley already has an Emoji that works. Its just that its parsed into an image. Deleting the image from the field and entering the short code...

Okay, so I'm having an issue where specific content in a specific forum is triggering a user-sided error without an admin error log. One of my members is a moderator in a specific sub-forum. They attempted to create a new thread (with a prefix) but received a server error, not letting them...