As other commenters mentioned, the jakt language is self hosted as of a few months ago. If you look at the projects README and source code, you can see that it's currently transpiling to C++. It's also only been around since May of this year.
LibWeb very much exists, and is not a fork of anything. It lives in the SerenityOS project and is written entirely green field C++.
So in the far future, jakt will compile in machine code with the rust-written rust compiler (or a bootstrap jakt-written jakt compiler) and will generate native code for a libWeb and libJS that are able to browse youtube and disney+, that with a SDK not pulling a grotesquely and absurdely complex and massive c++ compiler.
LibWeb very much exists, and is not a fork of anything. It lives in the SerenityOS project and is written entirely green field C++.