I'm trying to figure out how to accurately capture the state of the web app by a URL, similar to something like https://jsfiddle.net/, where they create
https://jsfiddle.net/foobar123 a custom ID for the code you load, and you can share that with anyone and they can run the code. However, it's not a live, interactive thing, so it makes sense to do it that way.
But I'm wondering what games do. I don't really play games so I am not aware how browser-based games use the URL. I'm interested to know if, when you want to start back your game (I'm imagining WoW, though I've never played it), you just go to wow.com and click "start" or "join", and there is no URL involved at all. Or perhaps instead of that, you go to wow.com/123foobar to go to your last saved state, and it loads up the environment as it last was.
I'm not wondering for WoW specifically, just generally any game, if they use the URL to persist state, and if so, how (roughly speaking). Some simpler games like agar.io don't seem to use the URL; if you refresh, you lose your spot and have to start over.
I'm not really sure how a game could save the dynamically evolving state in a URL, which is why I'm interested to see if any of them do.
Another related example is a Collaborative Markdown Editor. I don't know if they dynamically change the URL though to reflect the state, I doubt it.