Fuente: WIPO "tomato" A focus system includes a processor configured to execute machine instructions to implement and operate the focus system. The processor provides a focus application for storage and operation on a user device; receives a request from the focus application to provide content for display on the user device and a corresponding focusable user interface (U/I) listing elements referencing individual content items in the content to be provided, and transmit the requested content and a data structure from which the focusable U/I may be generated. The data structure includes data corresponding to the content items, which allows the focus application to construct and display the U/I as a focused U/I on the user device. The focused U/I includes spatial and Parent-Child-Sibling navigation rules for selecting elements of the U/I for focus, and element bubbling rules for refocusing an element for display as a focused element following a loss of focus condition.