[b]Note:[/b] When used for collision, [ConcavePolygonShape] is intended to work with static [PhysicsBody] nodes like [StaticBody] and will not work with [KinematicBody] or [RigidBody] with a mode other than Static.
[b]Warning:[/b] Using this shape for an [Area] (via a [CollisionShape] node, created e.g. by using the [i]Create Trimesh Collision Sibling[/i] option in the [i]Mesh[/i] menu that appears when selecting a [MeshInstance] node) may give unexpected results: when using Godot Physics, the area will only detect collisions with the triangle faces in the [ConcavePolygonShape] (and not with any "inside" of the shape, for example), and when using Bullet Physics the area will not detect any collisions with the concave shape at all (this is a known bug).