Very nice add-on. Improves the woeful default FF history experience. However, a couple things prevent it from receiving the full 5 stars:

* Time is displayed from right-to-left, rather than the more intuitive left-to-right, with no way to change. Very strange design decision.
* Missing full tab support.
* Some history doesn't seem to display on the timeline, but appears during a search.
* There are no settings whatsoever, only to clear history. Options to change font style, size, colour etc would be much appreciated.