Which component is essential to use when configuring a Pega Web Mashup gadget?

In configuring a Pega Web Mashup gadget, gadget parameters play a crucial role. They enable developers to customize the behavior and display of the mashup by passing specific values that dictate how the gadget interacts within its host application. For instance, these parameters can include the work object to display, the initial values for the user session, or settings for user interface elements.

Using gadget parameters ensures that the mashup behaves as intended within the context of the application it is embedded in, allowing it to leverage Pega's capabilities effectively while integrating seamlessly with the host environment. This flexibility is critical for achieving the desired functionality and user experience in a web mashup scenario.

In contrast, the other components mentioned, while they may have their own significance in different contexts, do not directly influence the configuration and customization of a Pega Web Mashup gadget in the same way that gadget parameters do. Access control lists are primarily concerned with permissions, third-party authentication deals with user validation across systems, and Document Object Model integration pertains to how web content is structured and manipulated. None of these are essential in the specific process of configuring the gadget itself.