@AdCharity thanks for your post. Observation #4 made the difference. Let me contribute a little:
My findings are in line with AdCharity's observations and findings. Here's what I did:
- I wanted to fork and play with the examples from stage.js. I imported https://github.com/shakiba/stage.js. This resulted in https://repl.it/@kkwoo/stagejs
- For better or worse, I renamed .replit to QUARANTINE.replit
- At this point, I still couldn't get the URL https://stagejs--kkwoo.repl.co to display anything
- Took me a while to realise that there's no index.html at the root directory. I created one with an HREF to the demo I want to play
That allowed me to achieve my goal of playing the Orbit demo and tinkering with it. It's not perfect because I now need to visit my hacked up /index.html and click through the HREF to see any changes I've made to the Orbit demo. A potential next step is to clone example/game-orbit/index.html into /index.html and change the relative URLs accordingly.