Check out:

- Maxthon - https://www.maxthon.com/mx5/features/dual-core/

- Midori - https://www.midori-browser.org/

I'd say the scenario is similar to Firefox/Gecko and Chrome/Blink. Sure there are clones that use the Gecko and Blink engines, but none of these really are as popular as their original.

I am waiting for another Opera / Presto browser platform to emerge. Till it did, the browser market dominated by Internet Explorer was literally stagnant. Opera with a Presto engine was a game changer with their light-weight and super fast browser engine with feature sets that all other browsers copied (and still lack even today).

I miss the plain UI speed of Presto-based Opera. I could cycle between tabs at my keyboard repeat speed - now my PCs are an order of magnitude faster and can't manage more than a couple tabs per second if I hold ctrl+tab.

Just tried this in FF and for what it's worth it cycles through the loaded tabs at keyboard repeat speed when holding down ctrl+tab.

When I do it I can see the URL cycling at my keyboard repeat speed (~30 fps), but the selected tab and page displayed in the foreground refresh about an order of magnitude more slowly. (1-5 fps) (So with a dozen tabs open, the effect is to select/show tabs in essentially a random order.)

edit: FF cycles smoothly (although with a weird white strobing effect with the main blank content area) if I open a bunch of blank tabs, but not if they're actual web pages.

It's the one reason I'm glad that all web browsers on iOS run Webkit.

Now if Apple could just fix their damn flexbox bugs and implement web app features...