> Are you saying their code was horrible and unsafe, or just that its a byproduct of using C++.

Yes.

It's both terrible because it's C++, and it's terrible because they're not following the modern C++ safe coding practices.

> They've been rewriting parts in rust: https://github.com/LadybirdBrowser/ladybird/blob/8f0a1b19114....

And it's not going to amount to anything major. Rewriting in Rust properly requires architecting things from the beginning.

> No they don't.

For a long time, their policy had been "no third-party code". Eventually it became untenable, so they started using third-party libraries. But they still ended up reinventing the wheel at least several times.