How to look into a room in 3D through the walls

Where3Dthe cluster of buttons at the bottom rightthe Walls: all shown. Click for dynamic button

Steps

Click Walls: all shown. Click for dynamic. Each click cycles the view: all walls, dynamic, walls hidden.
In the dynamic view, rotate the camera: the cut moves by itself to the walls that end up between you and the room.

Good to know

In the dynamic view, interior walls are always cut, and exterior walls are cut only on the camera side. A cut wall remains as a 26 cm band up from the floor; far exterior walls stay full height.
Where a cut wall meets a standing one, the end of the cut is flat, and the band rises to the standing wall with a slope.
The wall view is not saved in the project: another person will open the project with all walls shown.
A link to a finished room opens the 3D view straight in the dynamic view.