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The response from a component action request is typically, but not universally, used to send a redirect to the client; the redirect URL is a page render URL to display the response to the event. This is detailed under Request Processing Page Navigation.
RequestGlobals Service
The RequestGlobals service has a life cycle of per-thread; this means that a separate instance exists for every thread, and therefore, for every request. The terminators of the two handler pipelines store the request/response pairs into the RequestGlobals service.
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