>> 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.
You have that entirely backward. Linux distributions are the *only* ones that end up actually addressing library compatibility issues. Software vendors used to systems with no sensible library system (Windows and OS X) treat Linux exactly the same way, either because they want to have a pile of forked upstream libraries without pushing those changes upstream or maintaining a real library fork, or simply because they don't care about handling Linux correctly and the least common denominator requires shipping everything with the application.
Meanwhile, Linux distributions get stuck trying to figure out whether they can build each crazy upstream application against the system version of the library without breaking whatever crazy assumptions the bundled version allowed, and without rewriting large parts of the application's build system.