I've just merged https://github.com/mapeditor/tiled/pull/4288 which means the upcoming Tiled 1.12 will include support for capsule-shaped objects. See https://github.com/mapeditor/tiled/issues/2153 for the related feature request. These shapes should probably be imported as a [Capsule Collider 2D component](https://docs.unity3d.com/Manual/2d-physics/collider/capsule-collider/capsule-collider-2d-reference.html) in Unity.
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