Running from local file ??

It seems like you have opened this file by double-clicking on it. In order to test your build in a browser you need to load this file from a web server. You can either upload this file and the rest of the files from a Defold HTML5 bundle to a web hosting service OR host them using a local web server on your home network.

Learn more about running a local web server in the Defold HTML5 manual.

WebGL not supported ??

WebGL is not supported by your browser - visit https://get.webgl.org/ to learn more.