I ask because this has not been my experience writing several hundreds of thousands of lines of Rust code, nor has this been the experience of anyone I have helped get up to speed. Moreover, I believe there is no feature in Rust that is not necessary to achieve safety without sacrificing performance.
Just a very concurrent browser engine ;) One that does everything in parallel. Basically every task that can be parallelized becomes parallel (rendering, JS execution, CSS matcher, etc.).
Also you can, there is Github for Servo (said parallel browser engine project by Mozilla).
I ask because this has not been my experience writing several hundreds of thousands of lines of Rust code, nor has this been the experience of anyone I have helped get up to speed. Moreover, I believe there is no feature in Rust that is not necessary to achieve safety without sacrificing performance.