If is possible only rendering video texture, when I use On-demand rendering?

[hecodeit]

For better performance, I use On-demand rendering, as setting frameloop="demand".

Can I use video texture, and only updating video part? Keep rest of scene don't update?

I know it's like IMPOSSIBLE if canvas looping for video texture, how it "keep still" in the meantime? So how if I setting second "Always loop canvas" on top of the "On-demand canvas"? Or CSS3DRenderer on top of WebGLRenderer?