I wonder how many trillions in GDP we missed out on due to them building a monopoly in the browser space and then abandoning it. You can't imagine how happy I was in 2005 when Microsoft announced they were resuming development on IE. I was already a fan of Firefox by that point, but a lot of web dev was such a drag because you couldn't just use modern browser features--you had to accommodate all the users still browsing with that dinosaur.

Here's an archive of their momentous blog post:

https://forums.anandtech.com/threads/ie-update-to-debut-ahea...

They shipped a beta later that year, but the full release arrived in late 2006. That was 4 years since their prior release, an eternity in those days!