L-profiles are in the 90-degree module, and they are attached to each other. To achieve something in the corner, the left one is placed snug against the right one, edge to edge with the outer sides. With the existing angle, it will be tight between the elements. The fastening parts then need to be bent at the same angle to pull the elements together. With such an assembly, there will be 100% bracing in the corner, and for it to give way, essentially everything must give way.