BSP brushes cannot be selected through other BSP brushes that are set to hidden through the world outliner. Other assets such as static meshes are unaffected by this or do not cause the same error to occur.
1. Open Editor (any project)
2. Place two bsps in level in a line using Modes>placement>bsp
3. Face camera so that one of the bsps is behind the other.
4. In the world outliner, select the bsp brush closest to the camera.
5. Press the eye icon in world outline to cause brush to become hidden.
6. In viewport, try to select the visible bsp brush by selecting it through the area the original bsp brush is located within.
The visible bsp brush cannot be selected.
The visible bsp brush is selected.
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