I see two errors in the console. The first:

    ReferenceError: genDataFromText is not defined

This is because genDataFromText is defined inline in the main page after shaderoo.js loads.

Edit: now that I think about it, just because shaderoo.js is loaded first, doesn't mean getDataFromText will by called immediately. I don't have the time to debug or even just read someone else's code right now, so I'll just leave it at that.

The second:

    NotAllowedError: The play method is not allowed by the user agent or the platform in the current context, possibly because the user denied permission.

Alas Firefox is failing to tell me where exactly in the code the error is coming from.

I also see this warning:

    Loading failed for the <script> with source “http://127.0.0.1:8081/socket.io/socket.io.js?_=1585039727308”.

That's true, I'm not hosting anything on http://127.0.0.1:8081 :eyeroll: