A data processing system implements displaying a tabbed user interface comprising a plurality of tabs for navigating among a plurality of electronic documents; determining a first tab of the plurality of tabs is associated with a first tab group according to a first grouping criterion; and causing a first tab group control element to be displayed proximate to the first tab, the first tab group control element providing a set of tools for accessing content associated with the first tab group and for creating new tabs associated with the first tab group.