click play in the top right after it loads.
You can pretend you're a fireman and throw sand on it to make it stop before it destroys too much.
Having a background\career where I've never professionally developed software for the browser or using browser\web tools and frameworks but often interact with people that do ("sofware engineer" now is mostly people building web applications), I'm glad to see this acknowledged. The web is a great deployment platform, and browser focused tools are great for certain types of applications, but there are a lot of people that act like the browser (and by association, browser focused tools and languages) is the only way to write and deploy software. Often there are better tools available, especially if you're doing game like or simulation like software even if your main target is the browser. I've always felt most productive when building small things or prototypes in lightweight frameworks with a simple update\draw loop (Processing, Pico 8, Love 2D, C-Toy, etc.)