That second 'instance' (it actually keeps only one instance running) might not be helping in bringing up your windows. Try clearing your (startup/local) cache,

That second 'instance' (it actually keeps only one instance running) might not be helping in bringing up your windows. Try clearing your (startup/local) cache, it might have become really big. I do that whenever my Firefox takes long times to start - if you check in Process Monitor, at that time it is dealing with those cache folders.