Abstract: An extensibility model is used to provide active and interactive functionality in communication items, but the embodiments are not so limited. A computer system of an embodiment includes components configured to identify one or more activation triggers that operate to activate gadget code using an isolated code execution environment as part of injecting content into an email communication. A method of one embodiment provides an extensibility framework for using defined gadget triggers and associated gadget functionality as part of automatically injecting content inline with a mail message.

Abstract: A computing device provides a first server. The first server receives a primary request associated with a client. In response to receiving the primary request, the first server processes the primary request to generate a response message. As part of processing the primary request, the first server sends a secondary request to a second server after a delay period expires. The second server accesses a resource as part of processing of the secondary request. The duration of the delay period depends at least in part on a recent latency level of the client with regard to the resource. In this way, the first server throttles access to the resource.