Let's say one has 4 or Desktops. Edge is open in #1. I has multiple tabs (sites) going. Rt Clk on one of them > Move to new window. Now, when it is moved to whatever desired Desktop one has Edge in more than one (Desktop)... and just repeat to put it in as many as wanted. The ability to have the browser open in all Desktops is not restricted to IE... One can do the same w/ Edge.
Glad I discovered this.