diff --git a/index.html b/index.html
index c0627aa4..c28851f6 100644
--- a/index.html
+++ b/index.html
@@ -812,6 +812,12 @@ <h3>Endpoints</h3>
   <td><a>Fullscreen Window</a></td>
  </tr>
 
+ <tr>
+  <td>POST</td>
+  <td>/session/{<var>session id</var>}/window/consume-user-activation</td>
+  <td>[=Consume user activation of Window=]</td>
+ </tr>
+
  <tr>
   <td>GET</td>
   <td>/session/{<var>session id</var>}/element/active</td>
@@ -4039,8 +4045,43 @@ <h4><dfn>Fullscreen Window</dfn></h4>
   context</a>.
 </ol>
 </section> <!-- /Fullscreen Window -->
-
 </section> <!-- /Switch To Window -->
+<section>
+  <h3><dfn>Consume user activation of Window</dfn></h3>
+
+  <table class="simple jsoncommand">
+    <tr>
+    <th>HTTP Method</th>
+    <th>URI Template</th>
+    </tr>
+    <tr>
+    <td>POST</td>
+    <td>/session/{<var>session id</var>}/window/consume-user-activation</td>
+    </tr>
+  </table>
+
+  <p>The <a>remote end steps</a> are:
+
+  <ol>
+    <li><p>If the <a>current top-level browsing context</a> is <a>no longer open</a>,
+    return <a>error</a> with <a>error code</a> <a>no such window</a>.
+
+    <li><p><a>Handle any user prompts</a> and return its value if it is an <a>error</a>.
+
+    <!--
+      WARNING:
+      We use explicit data-cite here because this spec is still heavily dependent on the
+      old concept of browser contexts. DON'T COPY THIS PATTERN!
+    -->
+    <li><p>Let |window| be <a>current browsing context</a>'s <a data-cite="html#nav-window">active window</a>.
+
+    <li><p>Let |consume| be true if |window| has [=transient activation=] or false otherwise.
+
+    <li><p>If |consume| is true, [=consume user activation=] of |window|.
+
+    <li><p>Return <a>success</a> with data |consume|.
+  </ol>
+ </section> <!-- /Consume User Activation of Window -->
 </section> <!-- /Contexts -->
 
 <section>