The OCPL Tracker Firefox Extension monitors your list of items borrowed from the Orange County Public Library system in Orange County, California. You must have an OCPL library card and PIN to use this extension. It creates a status bar item with an icon and text indicating the number of days until your first item is due. The tooltip (hover text) shows a summary of how many items are checked out, when they come due, and whether you have any items on hold that are ready for pickup. It will optionally remember your library card number and PIN (using the Firefox Saved Passwords system), and will re-check your account every 24 hours, or on demand.