Just how do you "fix a segfault" in your page? Do you immediately replicate the user's exact computing environment, all down to the specific operating system and perhaps browser plugins which might contribute, install a specific version of the this obscure browser (Conkeror?) with debug symbols, fire up GDB and understand why the complex C++ crashed based on the core dump?
That seems like an unlikely amount of effort. IME If you have some "enterprise" tool with enterprise clients, there's typically going to be a list of browsers which are supported and tested by QA.
Having been in similar situations, I think he means that he does indeed replicate the bug (which isn't usually as bad as you make it sound) and then write different code that doesn't trigger that bug in the browser.
It isn't always possible, and in that case we do blame the browser in the end, but it usually is possible to work around it. It's ugly, but it's necessary to keep your customers happy.
That seems like an unlikely amount of effort. IME If you have some "enterprise" tool with enterprise clients, there's typically going to be a list of browsers which are supported and tested by QA.