Remote Browser Isolation in 2018

Hi HN! How would you build a remote browser like browserstack (cross os browser testing) nowadays? I started prototyping with noVNC (HTML 5 vnc client) & tigervnc but especially with the use of webgl, the load of a machine running dockerrized Ubuntu xfce easily gets >60 % on an 4core i7 16gb server.

Next I found the amazing GTK Broadway, have you ever used it? It brings GTK apps into the browser. You can seamlessly use libre office in your browser by just starting it with two environment variables (and the Broadway daemon) BUT it was impossible for me to find a working webgl Bowser purely running on GTK (epiphany etc all crash in Broadway when webgl content is present) or even use webgl in webkitgtk.

The next thing Im looking into is screen sharing via websockets and remote controlling the remote browser with something like node-remote, which basically just captures the mouse movements on a website and sends it over to the server, but the delay seems bigger even when sharing on the same machine in two browsers.

I've ready about qt being able to stream via webgl to expose UI via the web, but I could not find any runable demo of it.

I think remote browser isolation is a great tool for security, experimentation, hiding the origin of content , working on other OS , working on software not supported on the local env, or even bringing technologies like webgl to non supported browsers.

I'm Keen if there's something I haven't heard of in 2018, if someone knows about how browserstack is build that would be so much of interest, as I somehow can't believe that they put so much resources into their service as my current approach (VM with VNC)