Playground bug: "Error rendering panel: Registry item does not exist: notes/simple"

[corinnemayans]

I created a new account to test out the playground. I ran into this error on the Sidebar playground blueprint. I think this was pretty much just the happy path through, though I remember running into an issue where my browser hung while I was making a screen capture and I might have ended up going backwards and visiting the blueprint over again (in case that info helps with diagnosis).

Slack thread about this:

[twschiller]

Additional conversation: https://pixiebrix.slack.com/archives/C0436P48QHY/p1664488728556519