My niece asked me if I could do anything for her old Vista notebook. Aside from re-OSing it with XP or 7, I did the usual kill-stupid-services and malware scan. The drive activity light is always flashing. I looked in the Resource Monitor, and most of the activity is on .sqlite or .sqlite-journal files in firefox???
urlclassifier3.sqlite and .sqlite-journal
places.sqlite and .sqlite-journal
cookies.sqlite and .sqlite-journal
I would guess that it keeps history and cookies in a sqlite database, but why would the system have 95% busy disk IO mainly on these files?
Firefox is certainly becoming a bit overblown so I'm not too surprised. However, reinstalling it afresh should help and there's no need to lose saved form data and Bookmarks, etc.. Export them all to IE temporarily then get rid of FF including any application data before getting a download of the latest version.
I believe this week's version is 16.0.2 but it is only Sunday.