NeXTSTEP 4.0 (twitter.com)

Interesting that WindowMaker adopted the window style from the unreleased NeXTSTEP 4.0. I always thought that the window and close buttons were original design changes made in WindowMaker.

Found an accompanying article: https://www.highcaffeinecontent.com/blog/20190522-(Dont-Fear...

I own a fully functional NeXT Cube. They were always a joy to use