When using DetachActor, the collision for the mesh is detached, but the mesh remains attached to the blueprint. This causes the mesh to fall through the floor while leaving the collision behind.
Regression (yes) issue (does not) occur in 4.11.2
Boxes fall to ground, once detach occurs, several attached cubes fall through floor. If player moves camera they can run into invisible boxes where the assets collision remains.
Several boxes detach and collide with floor.
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