Abstract: A client device requests, from a particular server, a document for presentation in a browser associated with the client device, and receives the document. The client device calculates one or more connection performance values for the document and determines whether the one or more connection performance values are below a threshold value. The client device sends, to another server, a request for another document, for presentation in the browser, where the request for the other document includes an indication of whether the one or more connection performance values are below the threshold value. The client device receives a first version of the other document when the connection performance is below the threshold value and receives a second version of the other document when the connection performance is greater than or equal to the threshold value, where the first version includes less rich content than the second version.

Abstract: Aspects of the subject technology are related to systems and methods for anticipating content domain names to be used by a browser. A system may be configured to detect network events while one or more web pages associated with a domain name are being loaded, identify, based on the network events, one or more content domain names that are associated with the domain name, and storing, in a data repository, associations of the one or more content domain names with the domain name. The associations of the one or more content domain names in the data repository may be used to initiate a Domain Name System (DNS) request for at least one of the one or more content domain names when a subsequent web page associated with the domain name is loaded by a browser.

Abstract: Various aspects of the subject technology relate to systems, methods, and machine-readable media for providing a customized background in a user interface based on a selection of a user login option. A system can be configured to identify at least a first user and a second user of a computing machine, display a first background for the first user in a user login interface comprising at least a first user login option for the first user and a second user login option for the second user, receive a selection of the second user login option for the second user, and replace, in response to the receiving of the selection, the first background for the first user in the user login interface with a second background for the second user.

Abstract: A client device requests, from a particular server, a document for presentation in a browser associated with the client device, and receives the document. The client device calculates one or more connection performance values for the document and determines whether the one or more connection performance values are below a threshold value. The client device sends, to another server, a request for another document, for presentation in the browser, where the request for the other document includes an indication of whether the one or more connection performance values are below the threshold value. The client device receives a first version of the other document when the connection performance is below the threshold value and receives a second version of the other document when the connection performance is greater than or equal to the threshold value, where the first version includes less rich content than the second version.

Abstract: Aspects of the subject technology are related to systems and methods for anticipating content domain names to be used by a browser. A system may be configured to detect network events while one or more web pages associated with a domain name are being loaded, identify, based on the network events, one or more content domain names that are associated with the domain name, and storing, in a data repository, associations of the one or more content domain names with the domain name. The associations of the one or more content domain names in the data repository may be used to initiate a Domain Name System (DNS) request for at least one of the one or more content domain names when a subsequent web page associated with the domain name is loaded by a browser.