My places.sqlite is 400MB, and just opening the history viewer is enough to cause Firefox to hang for several seconds. It's really not designed to store history

My places.sqlite is 400MB, and just opening the history viewer is enough to cause Firefox to hang for several seconds. It's really not designed to store history forever; I even had to change places.history.expiration.max_pages and places.history.expiration.transient_current_max_pages in about:config to prevent it from deleting old entries.