s/o to CefGlue, the C# bindings: https://github.com/space-wizards/cefglue

and before that Scaleform!

FiveM uses CEF and let's you replace much of the built in GTA V scaleform with it.

It's incredible what can be done but can be far less responsive than the scaleform it replaces, but this may partially be due to it being a third party mod to the game.

Minecraft Bedrock uses React + a "web-like platform" (I assume this means they've just implemented the bits they needed) for their UI: https://github.com/Mojang/ore-ui

Bedrock's interface also feels slightly more sluggish than Java's, Though its definitely faster than the other examples here.

Ironic when it's faster than Java almost every other way.

BeamNG does it, and their UI responsiveness is the worst I've ever seen. It runs at most 20fps and using it is straight up painful.