FWIW DR-DOS is also free, IIRC it was released as open source some years ago (i think OpenDOS is based on it) and it is a bit more compatible with MS-DOS than F

FWIW DR-DOS is also free, IIRC it was released as open source some years ago (i think OpenDOS is based on it) and it is a bit more compatible with MS-DOS than FreeDOS.