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If you save the file as an STL, then open it in Windows 3D Builder. It can be saved as a 3MF file as the default.
It will now open with Windows 3D Print.
@JACANT The 3MF format would still be useful I think as a way to have multiple objects in a single file. For example to prepare a multicolor print on a PRUSA MMU unit. Currently DSM will save as an AMF file which can be used in that same way, but it sounds like 3MF is the preferred format for some uses. The STL saved as a 3MF in Windows Builder combines the separate solids into a single solid I believe?