message: Call framebuffer.blit in StencilSystem.push
diff: @@ -62,6 +62,7 @@ export class StencilSystem extends AbstractMaskSystem
  maskObject.renderable = true;
  maskObject.render(this.renderer);
  this.renderer.batch.flush();
  + this.renderer.framebuffer.blit();
  maskObject.renderable = false;
  this._useCurrent();
  