My experience* is that Firefox has many more bugs than Chrome, Firefox bugs take much longer to be fixed, and users are more likely to be using older versions of Firefox so bugs affect us for longer.
In 3 years our webapp has been affected by very few Chrome specific bugs none of which caused us serious problems, or hard to work-around. Chrome has fixed bugs that affected us within a release or two (not years).
Currently our app has about 4 Firefox specific work-arounds. The worst was opened in 2004 and last month took me over 20 hours work to diagnose due to it only affecting us under specific circumstances: https://bugzilla.mozilla.org/show_bug.cgi?id=263945
* we have a complex pure JavaScript front-end, 95% written by me, with no library dependencies (because we started with scriptaculous many years ago, and outgrew it).
In 3 years our webapp has been affected by very few Chrome specific bugs none of which caused us serious problems, or hard to work-around. Chrome has fixed bugs that affected us within a release or two (not years).
Currently our app has about 4 Firefox specific work-arounds. The worst was opened in 2004 and last month took me over 20 hours work to diagnose due to it only affecting us under specific circumstances: https://bugzilla.mozilla.org/show_bug.cgi?id=263945
* we have a complex pure JavaScript front-end, 95% written by me, with no library dependencies (because we started with scriptaculous many years ago, and outgrew it).