Seems to put Chrome/Safari/Firefox browsers into a blank loop for now

Fixed, webcode changed its URL structure and it broke

OOOH you forked it! I am excited by what you do. I personally found this notebook very hard to debug, but also it has a lot of potential with the service worker. In retrospect it was a mistake working of the .tgz, I think these days I would try to provide an offline view over (unpacked) backups hosted on github https://github.com/endpointservices/observable-notebooks

Indeed: it works impressively great as long as you call the fork "offline" (because of the regex). Still a hobby problem but I needed specific file extensions packaged into the service worker to take pyodide offline. A challenge to debug though, yep. Anyway, good first deeper experience with webcode.run!

Oop, ran into an iOS issue where the service worker setup re-downloads the tgz many times, maybe because of cache misses, and had to hang this up. Okay starting place though. Service workers are tricky.