Hmmm. I have kludge set on in the BBS.
In the message base settings you have an option to strip kludge when mutil processes the messages.
I turn mine on, because its helpful when troubleshooting, if needed.
--- Mystic BBS v1.12 A43 2019/03/02 (Linux/64)
* Origin: The ByteXchange BBS | bbs.thebytexchange.com (21:1/107)