ROOMS, developed at Xerox PARC with Interlisp-D, is what we now call a virtual desktop manager. In this 1987 videotape its creators Austin Henderson and Stuart Card present and demostrate the system.
https://www.youtube.com/watch?v=_WL9IRPOZ8c
To learn more about ROOMS see this overview paper:
https://dl.acm.org/doi/abs/10.1145/24054.24056
And the manual: