In general, the subject matter described in this disclosure can be embodied in methods, systems, and program products for changing a reference to a bookmark icon. The method includes receiving resources that include an HTML document and computer program script code. The HTML document does not include a reference to a bookmark icon. The method includes determining that the computing device has loaded the web page and, in response, adding, in a representation of the HTML document, a reference to a first bookmark icon. The method includes receiving a request to change a display of the web page from a first screen to a second screen, without requesting additional resources over the network. The method includes removing the reference to the first bookmark icon in the representation of the web page, and adding a reference to a second bookmark icon in the representation of the web page.