To reproduce:
1. Create a new project.
2. Create Empty game object.
3. Add "Cloth" component to it.
4. In "Skinned Mesh Renderer" select any default mesh (for example Sphere)
5. Now Select a different mesh. (for example Plane)

Expected result: Mesh looks normal.
Actual result: Mesh looks different than it should.

Reproducible: 5.5.0a6, 5.5.1f1, 5.6.0b7
Not reproducible: 5.4.3p1

Workaround:
It fixes itself when Play is pressed. Or when "Cloth" component is removed.

Also it gives 2 errors:
[Physics.PhysX] PxScene::addActor(): Actor already assigned to a scene. Call will be ignored!
UnityEditor.HostView:OnGUI()

[Physics.PhysX] PxScene::addActor(): Actor already assigned to a scene. Call will be ignored!