Does the Firefox data source duplicate Firefox's history storage?

I've installed (and since deactivated) the Firefox data source for Zeitgeist, and found that Zeitgeist only shows sites visited while the Firefox data source was installed and active.

From what I can guess, this means that the data source is not providing Firefox history information to Zeitgeist. Instead, the Firefox extension is sending events to the Zeitgeist logger daemon about every Firefox page visited, and the Zeitgeist log is getting populated with a URI, a date/timestamp, and other relevant information separately from similar information being stored in the Firefox history database.

Am I correct?