Although not full operating systems, since at least 2005 there were also some solid systems using similar concepts (not Windows though), like eyeOS [1]. [1] ht

Although not full operating systems, since at least 2005 there were also some solid systems using similar concepts (not Windows though), like eyeOS [1]. [1] https://en.wikipedia.org/wiki/EyeOS https://en.wikipedia.org/wiki/EyeOS