Not sure if this is what you’re looking for, but you can add Nested Desktop as a non-Steam game and access it from Gaming Mode. Makes it so you can switch between games and Desktop without having to exit the game too. You might have to tinker with controls and the dim/sleep power settings.

It wasn’t. He had previously said that he would open source it after it had become more stable, but there was a lot of skepticism that he would follow through.

A key to mushrooms that grow on other mushrooms