I work at a company that has been doing a webkit-based GPU accelerated renderer for more than 4 years and we have great results powering many games with <1ms render times for many cases. Webkit however has a lot of intrinsic architectural limitations that we spent a lot of time trying to overcome. Now we are writing a new HTML renderer from scratch and our results are promising: 5x-12x faster than anything WebKit/Blink based. You can hear more about how that was done at CppCon 2018 (https://cppcon2018.sched.com/event/FnKC/oop-is-dead-long-liv...). Also I would love to hear from people interested trying Electron-based apps with our tech.