Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for managing access to public content are disclosed. In one aspect, a method includes receiving, at a user device, first content transmitted by a first system; in response to receiving the first content, generating, by the user device, a request for second content; transmitting the request for the second content to a second system; determining, by the user device, whether the second content has successfully loaded; and in response to determining that the second content has not been successfully loaded by the user device, executing code included as part of the first content to cause a display of main display content. Other embodiments of this aspect include corresponding systems, apparatus, and computer programs, configured to perform the actions of the methods, encoded on computer storage devices.