If a bsp is converted to a blocking volume, the faces of the bsp remain present until a new actor is placed or geometry is compiled.
1. Open editor (any project)
2. Open modes>placement>bsp>place bsp box into level
3. Select bsp>details>convert>blocking volume
Faces of bsp brush are still present and visible. Building geometry and/or placing a new actor removes faces.
Faces of bsp brush are removed from blocking volume.
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