In those days, DOS was the OS. Windows and DESQview were just window manager apps that ran other apps.
What is that? I don’t think that’s what I had in mind. I think it’s DESQview I was trying to think of. Anyway, not important… it was just driving me nuts I could not remember.
To be fair, I was quite vague. I think there are multiple right answers… but I recalled one starting w/a ‘D’ and that’s what I was trying to recall.
No, I figured if I could recall the name I could get a nostalgic fix by searching it. I found this:
https://en.wikipedia.org/wiki/DESQview
I recall DESQview was much lighter weight and better performing than Windows, but had limitations. I did not recall that the windows were text only within, but that’s starting to fill some holes in my memory.

