Found out that CrosseyedWebGLRenderer probably wouldn't work for target-less cameras.
Something weird going on with `webgl_scene_test.html` and `webgl_scene_test_blender.html`. For some reason cubes dissapear.
I think setViewOffset is mostly useful for multiple monitors
synced across multiple machines but that's a hard demo to setup
so these demos show doing it locally with muliple canvases