I would consider that an issue with the software. Non-manifold models, or self-intersecting models, are not suitable for 3D printing. This is an issue with the

I would consider that an issue with the software. Non-manifold models, or self-intersecting models, are not suitable for 3D printing. This is an issue with the model rather than the file format. If 3MF somehow makes self-intersection, and non-manifoldness, impossible cannot we run STL files though the same algorithm to end up with a "fixed" mesh? What happens if you try to save a non-manifold model as 3MF? Will it magically fix the issue or will it fail to generate the file?