The new operation is as follows:

Step 1: Move the mouse to the "Mode" in the upper menu bar and select the point selection mode;

Step 2: Left-click with the mouse to select the points on the same side of the cabinet;

Step 3: Right-click on the cabinet - select the line - top line / bottom line installation;

Step 4: Select the style and material, and modify the section height.

Operation completed: