A builder on our team has been frustrated by the following bug.
When importing a mesh (by inserting a meshpart and clicking the MeshId), he will scale and position the mesh in the world. 20-50 studio “actions” later, he does a “CTRL-Z” and the meshId will be missing.
The 20-50 studio actions did not involve the part that turned invisible.
Windows 10, in a team create session.
Notice the mesh visible here (large skeleton):
Later becomes invisible (bounding box still there):