Merge pull request #2358 from w3c/editorial/issue-2355

Clarify svg title phrasing content restrictions

epub33/core/index.html

@@ -5981,12 +5981,16 @@ <h4>Restrictions on SVG</h4>
  </ul>
  </li>
  <li>
- <p id="confreq-svg-title">The [[svg]] <a
- href="https://www.w3.org/TR/SVG/struct.html#TitleElement"><code>title</code></a>
- element MUST contain only valid <a href="#sec-xhtml-req">XHTML content document Phrasing
- content</a>.</p>
+ <p id="confreq-svg-title" data-cite="svg">If the [[svg]] [^title^] element contains
+ marked-up text, the markup MUST contain only elements declared in the <a
+ data-cite="dom#html-namespace">HTML namespace</a> [[dom]].</p>
  </li>
  </ul>
+ <div class="note">
+ <p>Although the [[svg]] <code>title</code> element allows markup elements, support for this
+ feature is limited. [=EPUB creators=] are advised to use text-only titles for maximum
+ interoperability.</p>
+ </div>
  </section>
  </section>
 
@@ -11440,9 +11444,9 @@ <h3>The <code>application/epub+zip</code> media type</h3>
  <p>This appendix registers the media type <code>application/epub+zip</code> for the EPUB Open Container
  Format (OCF).</p>
 
- <p>An OCF ZIP container, or EPUB container, file is a container technology based on the [[zip]]
- archive format. It is used to encapsulate the EPUB publication. OCF and its related standards are
- maintained and defined by the <a href="https://www.w3.org">World Wide Web Consortium</a> (W3C).</p>
+ <p>An OCF ZIP container, or EPUB container, file is a container technology based on the [[zip]] archive
+ format. It is used to encapsulate the EPUB publication. OCF and its related standards are maintained
+ and defined by the <a href="https://www.w3.org">World Wide Web Consortium</a> (W3C).</p>
 
  <dl class="variablelist">
  <dt>MIME media type name:</dt>
@@ -11576,6 +11580,8 @@ <h3>Substantive changes since <a href="https://www.w3.org/TR/2022/CR-epub-33-202
  Recommendation</a></h3>
 
  <ul>
+ <li>14-July-2022: Clarified that the markup in the SVG <code>title</code> element is restricted to
+ HTML elements. See <a href="https:/w3c/epub-specs/issues/2355">issue 2355</a>.</li>
  <li>10-June-2022: Clarified that data blocks are exempt from fallback requirements. See <a
  href="https:/w3c/epub-specs/issues/2331">issue 2331</a>.</li>
  <li>07-June-2022: The usage of File URLs has been disallowed. See <a