Actually gecko's clumsy codebase is the reason why firefox still does not have features like process-per-tab, and why a heavy web-app in one thread can destrroy the browsing experience of another tab (as everything is strictly single-threaded).
They have a project named Servo to replace to Gecko, they even designed their own programming language to write it in (Rust).
I have hundreds of tabs open in Firefox right now, in multiple tab groups . . . Chromium would fall flat on its face here.
Yeah that's how everyone browses, so running with hundreds of tabs should shoot right up to the top of the priority list. I mean how can anyone get anything done on the internet unless you have hundreds of tabs open. I hear there are REALLY cool people out there who have THOUSANDS of tabs open. Someday we will have to use 64-bit integers to describe how many tabs we can have open at once. The eventual goal is to simultaneously open every single web page on the entire internet in its own tab, all at once.
Well yeah, if you take out the fact that it's an interpreted language.