If a bsp brush is rotated, then the brush clipping feature is used the "Brush Clipping" feature will rotate the created face by 90 degrees or disappear entirely (if set at an angle).
1. Open Editor (any project)
2. Create a box bsp brush
3. Change the following Brush settings(For better bug visibility)
4. Rotate the box 90 degrees
5. Select geometry editing mode
6. Select brush clip with bsp brush selected in viewport
7. In Orthographic view, press spacebar, drag the brush clip out and press spacebar again across entire bsp brush straight across the z axis
8. Select Apply
Face rotates 90 degree when bsp is clipped.
BSP is clipped, faces do not rotate.
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