I'm not sure if there's a saltwater invert
section but there must be,one thing.i do know is that mantis will kill almost anything and from reading here they are kept on their own, muscle,crab,cockles or anything like that don't stand a chance, there are a few videos here showing them in action, they've also been known to crack tank glass, not sure how much of this you know but please ignore it if you do, I'd love to keep one
As to the topic of Mantis shrimp.
It depends on the type of mantis, a smasher or a spearer.
I had a hitch-hiker smasher, which wasn't a problem, until it started devouring my inverts. All my shrimp, snails, anything with a shell was a gonna.
Spearers will target fish, and can destroy a community reef tank fish population.
To me, mantis shrimp are some of the most intelligent creatures this planet knows, and if you want to keep one as a pet, then yes, do so (they're really cool), but I would suggest they be kept in a tank of their own. They are too clever to risk in a community tank. The caveat, a smasher in a fish only with no inverts should work out ok.
The smashing of aquariums is largely anecdotal, and whilst a smasher 'could' break a tank, unless you antagonise it, it's unlikely to happen
I personally wouldn’t keep one in my tank if it was a hitchhiker. Does that mean you should kill it no. I had a QT tank that I could have moved it to, I had a refugium and a sump as well. All would have housed one had I chosen to keep one. You can also catch it and sell or give it away. Or you could also set up a small tank for it.
There were many hitchhikers that I killed when I had my reef tank just because they were bad and no one would want them. Keep this in mind as it is part of the hobby IMO. A mantis shrimp doesn’t fall uNader the category of an immediate kill IMO. There are other outlets for them.
I would definitely not keep a Mantis Shrimp of any kind in a reef tank simply because they are predators by nature. IMHO they are best suited to their own tanks (smasher or not). Just set up a small tank for it and call it good.