This should be required reading for anyone who thinks that frontend is easy.

Also, if anyone thinks this is a limitation of the web, I'd challenge you to try to create an app that displays 18,000 lines of syntax-highlighted, findable text using another popular toolkit like .NET, Qt, or Cocoa. They'll all get bogged down if you try to naively put all of that content in a single view and expect built-in scrolling and find features to just work, quickly. Pretty much the only way to make something like that work involves a lot of tricks behind the scenes, no matter what platform.

I'm really happy they landed on a solution that not only delivers high performance, but supports the browser's native Find function and accessibility. I think some people could have anticipated those problems, but far more important is that they listened to user feedback and pivoted when their first idea didn't make users happy.