diff --git a/source b/source
index f39415a8c8e..9fc456420f1 100644
--- a/source
+++ b/source
@@ -3928,6 +3928,8 @@ a.setAttribute('href', 'https://example.com/'); // change the content attribute
 
     <ul class="brief">
       <li><dfn data-x-href="https://drafts.csswg.org/css-fonts/#first-available-font">first available font</dfn></li>
+      <li><dfn data-x-href="https://drafts.csswg.org/css-fonts-5/#text-scale">text-scale</dfn></li>
+      <li><dfn data-x-href="https://drafts.csswg.org/css-fonts-5/#text-scale-meta-keywords">text-scale keywords</dfn></li>
       <li>The <dfn data-x-href="https://drafts.csswg.org/css-fonts/#font-family-prop">'font-family'</dfn> property</li>
       <li>The <dfn data-x-href="https://drafts.csswg.org/css-fonts/#font-weight-prop">'font-weight'</dfn> property</li>
       <li>The <dfn data-x-href="https://drafts.csswg.org/css-fonts/#font-size-prop">'font-size'</dfn> property</li>
@@ -18283,8 +18285,37 @@ interface <dfn interface>HTMLMetaElement</dfn> : <span>HTMLElement</span> {
     how CSS fallback works for properties, the multiple meta elements needs to be arranged with the
     legacy values after the newer values.</p>
    </dd>
-  </dl>
 
+   <dt><dfn attr-value for="meta/name"><code data-x="meta-text-scale">text-scale</code></dfn></dt>
+
+   <dd>
+    <p>The value must be a string that matches one of the <span>text-scale keywords</span> defined for the
+    <span>text-scale</span> metadata name in the CSS Fonts specification.</p>
+
+    <p>There must not be more than one <code>meta</code> element with its <code
+    data-x="attr-meta-name">name</code> attribute value set to an
+    <span>ASCII case-insensitive</span> match for <code
+    data-x="meta-text-scale">text-scale</code> per document.</p>
+
+    <div class="example">
+     <p>The following declaration indicates that the page is aware of and can handle the user's
+     text scaling preferences:</p>
+
+     <pre><code class="html">&lt;meta name="text-scale" content="scale"></code></pre>
+    </div>
+
+    <div w-nodev>
+
+     <p>If any <code>meta</code> elements are <span data-x="node is inserted into a
+     document">inserted into the document</span> or <span data-x="node is removed from a
+     document">removed from the document</span>, or existing <code>meta</code> elements have their
+     <code data-x="attr-meta-name">name</code> or <code data-x="attr-meta-content">content</code>
+     attributes changed, user agents must process the <code>meta</code> element's state as defined
+     in CSS Fonts.</p>
+
+    </div>
+   </dd>
+  </dl>
 
 
   <h5>Other metadata names</h5>