> Indeed. But the bigger issue, I think, is: what makes Firefox and Chromium so special that they have to pop out a major new, compatibility-busting release every few months?
It's probably related to the issue of how Linux distributions can't give enough of a crap to put serious effort to care about binary compatibility with applications. You know; so it's possible for software vendors to provide and users to take advantage of newer features in newer software and/or rely on proven older software without tearing their hair out.
It's probably a lot easier for Mozilla and Google to simply bundle the dependencies they require with their software then it is leave it up to the distributions and package management systems to do it for them.