Very interesting paper. I was a bit puzzled, though, at the assertion related to the Stepstone graphics libraries that X11 was still "years away". The chronolog

Very interesting paper. I was a bit puzzled, though, at the assertion related to the Stepstone graphics libraries that X11 was still "years away". The chronology of the paper is not 100% certain in that area, but my impression was that this assertion was set in something like 1987/88, and X11 was released in late 1987.