The documentation appears to be absent for the 100gbps flagship switch!
I was just putting together a proposal to use them as our TOR switches for a datacenter move at the end of the year and realized I didn’t have specifications for jumbo frame support.
I’ve looked several places, and I believe this is the most complete place to find MTU for various devices:
https://help.mikrotik.com/docs/spaces/ROS/pages/21725296/MTU+in+RouterOS#MTUinRouterOS-MAC/Layer-2/L2MTU
Anybody care to share the maximum MTU they have tested, or can configure?