Rated 5 out of 5 stars

Though every front end developer must have Firebug, back end developers get less out of Firebug. FirePHP brings the usefulness of Firebug up to where it is for front end developers. Sort of like magic, but easier to use: no wands or smelly potions needed.

This review is for a previous version of the add-on (0.0.6.23).