And in hindsight it doesn't seem a terribly good example.
Gecko was a technical success.
On the non-technical side, it isn't at all clear that Netscape-the-company came out worse than it would have done if it had tried to stick with the buggy Netscape 4 rendering engine.
I'd argue that their attempted rewrite of Firefox in Rust also caused them to actually fall behind in terms of features and speed, which is reflected in the diminishing market share of Firefox. Technologically Rust is an awesome language and a boon to secure software development, I'm just not sure it was such a great idea for Mozilla to put so much energy into this, which could've gone into improving their main product instead.
Chrome was absolutely faster in web rendering than Firefox and more stable and the UX was cleaner, it made Firefox with its slow buggy performance and awful theme's look like myspace to Chromes facebook.
I also remember being very frustrated with Firefox on Ubuntu ~10.04 at the time and when Chrome came along it was exactly what I'd been waiting for.
Quantum/Servo/Rust/UI refreshes seems like this was Firefox catching up to Chrome v1 and honestly in 2020 it feels like Firefox has finally caught up significantly.
It's still not as stable as Chrome but it's getting there, webrender is a massive leap forward in performance:
I know 3 examples from personal experience. One that I worked on myself, that was scrapped before completion. Two other two were finished but they have severely impacted the business. But they are not so useful to share because you would not know about these products. My assumption is that we all know these kind of projects, but the Netscape story is a great reference because it explains why it is a bad idea.
