I play a lot of windowed games on my PC as I watch less engaging content like TV I’ve seen, Youtube. Lately Balatro, Peglin, a racing game called art of rally, Mini Motorways. Interested to hear other people’s preferences.
I generally want something that runs well windowed because I use a third of my ultrawide to run the video, so no shooters or “big” games usually.
I played it on mobile but it’s on pc as well- Slice & Dice. A really fun dice based roguelite. Liked it a little more than peglin and balatro.
Lately I’ve been playing Factorio a lot with something on my other monitor but idk if it meets your criteria as well.