Many times I have encountered Firefox bugs that either haven't been reported, or which bugzilla's shit search makes too hard for me to find. Usually that's where I give up because it's a pain in the ass to enter reports in bugzilla, the whole process seems intended to scare off anybody not in the organization.
this does not mean that reporting more bugs would result in noticeable improvements, as likely there are already too many reported bugs to process them
at least that is my impression based on fate of my bug reports
