code: function createContext(canvas, opt_attribs) {
    const names = ["webgl2", "webgl", "experimental-webgl"];
    let context = null;
    for (let ii = 0; ii < names.length; ++ii) {
      context = canvas.getContext(names[ii], opt_attribs);
      if (context) {
        if (defaults.addExtensionsToContext) {
          addExtensionsToContext(context);
        }
        break;
      }
    }
    return context;
  }
docs: Creates a webgl context.
  
  Will return a WebGL2 context if possible.
  
  You can check if it's WebGL2 with
  
  twgl.isWebGL2(gl);
  
  @param {HTMLCanvasElement} canvas The canvas tag to get
  context from. If one is not passed in one will be
  created.
  @return {WebGLRenderingContext} The created context.