The strangler pattern (gradually replacing C++ with Rust) is pretty much the only alternative to a https://www.joelonsoftware.com/2000/04/06/things-you-should-... complete rewrite.

Some areas of code are more sensitive than others. Eliminating bugs in areas dealing with encryption, sandboxing, etc may be very beneficial.

Most of the fun stuff your computer is doing right now is the direct result of C and C++ code (browser, kernel, web server, games, etc.). Replacing all that code in one go isn't going to happen. Still, Rust solves some real problems with C++, so we shouldn't ignore it. If we can't replace the world all at once, why not do it piecemeal while targeting the highest value components?

You have to start somewhere. Every C++ component that's replaced by a safe Rust component is a reduction in attack surface.

That was the goal with Servo, but Mozilla axed them https://twitter.com/directhex/status/1293352458308198401

Servo was always a research project around writing a rendering engine and not an attempt to create a whole new browser product.

Webrender would work better as the complete OS interface than as an engine for one browser/app.

> If C++ is so important, then just stick to that?!

A journey of a thousand miles begins with a single step ...

Legacy is a thing. Replacing it piecemeal is the only way to get it replaced.

In addition, you can prioritize pieces. If a particular piece is very likely to be a security problem or has lots of bugs, you can rewrite just that piece into Rust.

If only a certain foundation's corporate half didn't fire its Rust browser developers.