https://www.brow.sh/
It renders anything that a modern browser can; HTML5, CSS3, JS, video and even WebGL.
The only dependency is a recent 57+ version of Firefox.
Hmmmm....... So, if it can use FF extensions and allow selection of additional features to be rendered such as images, embedded videos, links, etc it might make a lean & mean 'pro' browser that strips much of the eye-candy by default.