[WorldMaker]

The Sets experiment (heterogeneous tabs for nearly every Windows title bar) from the Windows team was really cool. I was sad that I was never in one of the Insider cohorts to directly test it.

It's unfortunate their testing feedback decided not to move forward with it, and that also the engineering complexities that happened because Edge switched to Chromium and would no longer be able to maintain some of the things Sets relied upon.

Rumors (er, GitHub Issues) have it PowerToys might explore the idea again some day.