 Also, today’s reading systems do not develop an HTML renderer themselves; they, rather, rely on external tools (typically a “WebView” implementation) that can be assumed to conform to the relevant W3C specifications.
        </p>

        <p>
          This means that these additional tests would be quite unnecessary for the purpose of testing the EPUB 3.3 specification (which is the main purpose of a <a href="https://www.w3.org/2021/Process-20211102/#RecsCR">W3C Candidate Recommendation</a>). As a 