Bash function to list the most visited websites on Firefox:

firefox_visits() (
  db=$(mktemp)
  [ -f $db ] || cp $(find ~/.mozilla -name places.sqlite {} +) $db
  echo "History count:"
  sqlite3 $db '.width 0 50' 'select printf("%8d", visit_count) visits, url from moz_places order by visit_count desc limit 10;'
)

Querying Firefox’s DB is a good way to recall SQL and gain useful browser data.