The story of web development:

"For the time being, I’ll just do what most web devs do: choose whatever API accomplishes my goals today, and hope that browsers don’t change too much in the future."

It's a strategy that's worked out very well. Standards groups and browsers prioritize backwards compatibility very highly. It's hard to remember any real compatibility breakages in standardized HTML/CSS/JS features (ie. not third-party plugins like Flash).