message: Expose the WebGL renderer internal canvas for debugging
diff: @@ -93,6 +93,10 @@ export class WebGLRenderer {
  return this._initWebGLContext();
  }
  + getCanvas(): HTMLCanvasElement {
  + return this._canvas;
  + }
  +
  private _releaseContextRelatedResources(): void {
  this._shaderProgram = null;
  this._vertexPositionAttrib = null;
  