> I don't think we want this to run at every startup. We could instead use a defaults.js file and have the default preferences there.

I tried doing that some this some time ago, but I could never get it to work. Then a found https://bugzilla.mozilla.org/show_bug.cgi?id=564675 (and http://starkravingfinkle.org/blog/2011/01/restartless-add-ons-%E2%80%93-default-preferences/), which seems to indicate that we unfortunately have to initialize these on *every* `startup`.