Reapply update after merge conflict.

Author: daobrien

index.html

@@ -53,13 +53,6 @@ <h3>
         <img class="social" src="font/fontawesome/svgs/brands/readme.svg" alt="Style Guide" width="40em" /> Red&nbsp;Hat Technical Writing Style Guide v5.1</a>
     </h3>
 
-    </h3>
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-      <h3>
-        <a href="https://stylepedia.net/docbook/4.0" title="DocBook XML Guide v4.0">
-          <img class="social" src="font/fontawesome/svgs/solid/code.svg" alt="XML Guide" width="40em" /> RHT DocBook XML Guide v4.0</a>
-      </h3>
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     <h3>
       <a href="https://www.redhat.com/en/about/brand/standards" target="_blank">
       <img class="social" src="font/fontawesome/svgs/solid/book-open.svg" alt="Brand Standards" width="40em" /> Red&nbsp;Hat Brand Standards</a>