Looks like playgrounds was integrated into canvas. The #Playground macro (in combination with import Playgrounds) is used to make a playground in the canvas. It's a shift in the way I use playgrounds as throw-away experiments. Now those will be part of my app code if I forget to remove them which will be an annoyance. See https://developer.apple.com/documentation/xcode/running-code-snippets-using-the-playground-macro

Additional: It won't launch an app on my phone either. (No changes to the app, and it would launch in sim or phone before the failed update of Xcode.) It's just spinning in "Launch" phase of the build.

I also sent an email to Apple dev support with Xcode as the tag with the above text. After first trying restarting Xcode, deleting and reading my account, etc, etc, then just throwing up my hands and doing something completely different for some hours I come back this evening and find that it's magically working. Xcode sees the new team name, profiles, etc, etc. I'm really glad and thankful that it's working. But the lack of visibility to the problem and lack of any obvious solution except waiting a magic amount of time (and perhaps sending an email) is a problem and is a single point of failure in the development process. Most of the time this adding a new team thing just works. But when it does fail, there's no way to fix it or see what's wrong.

I'm seeing the same problem with Xcode 13.2.1, but the above steps isn't fixing it. Anyone seen a further workaround yet? I'm trying: Quit Xcode quit simulator delete files as above killall as above. But I'm still getting preview not working.