When I set the CollisionFidelity property of a MeshPart without a MeshId to anything in the property explorer, after ~4 times or if I do it too fast, Studio stops responding and crashes.
This reproduces reliably if you insert a default meshpart and change the collision fidelity using the dropdown in the properties widget.
This does not occur for me when I execute a script to manually do that so it’s probably a bug related to the Studio widget system. Although I haven’t messed around with MeshParts in a while this is the first time this has ever happened to me.
Time of crash: 5/30/2020 2:25 PM EST
Video demonstration: