How do our definition of Web Page and the Robustiness section interact?
From my review: 4.1 Overview “This specification makes no specific assumption about the content with which the user interacts, except for one: There is a top-level Web page that is identified by a URI [RFC3986]. This Web page might be an HTML frameset, an application running on top of a proprietary run-time environment, or a document in a format interpreted by plug-ins or external systems served as part of a Web interaction. The page’s behavior might be determined by scripting, stylesheets, and other mechanisms.” And yet, I believe some of our recommendations (for example, in Robustness) become ineffective in the case of “a document in a format interpreted by plug-ins or external systems served as part of a Web interaction. “, since that executes code outside of the web user agent, which the previous paragraph defined. At the least, we should say that.