A lot of people in the comment section for Firefox mentioned a new browser currently under development called Ladybird. I checked its repository, and it says: 'Ladybird is in a pre-alpha state and only suitable for use by developers.'

https://github.com/LadybirdBrowser/ladybird

PS: I don't know much about the devs or team behind it but they already seems to have a big sponsors like Cloudflare https://ladybird.org/

GitHub - LadybirdBrowser/ladybird: Truly independent web browser

Truly independent web browser. Contribute to LadybirdBrowser/ladybird development by creating an account on GitHub.

GitHub

@nixCraft I personally think Servo is a better project to look forward to, it doesn't have weird people behind it like Ladybird does: https://servo.org/

It would be funny if the project took off and replaced Firefox since it was initially started as an engine replacement for Firefox but abandoned by Mozilla after a while.

Servo aims to empower developers with a lightweight, high-performance alternative for embedding web technologies in applications.

Servo is a web rendering engine written in Rust, with WebGL and WebGPU support, and adaptable to desktop, mobile, and embedded applications.

Servo
@Lenni @nixCraft sadly servo is million miles away from usability.
@janantos @nixCraft Ladybird also is from what I know. I've messed around with Servo's latest tagged releases and they actually worked for many websites, with some rendering issues, bugs and broken websites here and there, but overall it was really good considering how long it has been almost competely dead.