I will try to take a look at some point, but I have to say that in general, commercially supporting a product used by thousands of people over several years using 700+ lines of complicated code from a random person on the Internet often proves to be a nightmare, and our other experiments have run in to other bugs and limitations (like gamepad input not working) which I think would be a likely outcome here. It would probably work out a lot better if there was either support from Valve for WebView2, or better official support for render-to-texture for WebView2 (as this looks more of a hacky workaround).