diff --git a/doc/config.html b/doc/config.html
index 41eeb9e4..75e1e6b4 100755
--- a/doc/config.html
+++ b/doc/config.html
@@ -2550,6 +2550,12 @@ Options Location = Main Building{a}, New Building{b}, Old Building{c}
         If an entry with the same ID in the destination logbook exists already,
         it gets overwritten. Default for this setting is <b>0</b>.
       </li>
+      <li>
+        <b><code>Collapse to last = 0|1</code></b><br>
+        In threaded view, the list of replies can be collapsed into a single
+        entry. If this flag is 1, then the last entry of each thread is shown,
+        otherwise the first thread is displayed. Default for this setting is <b>1</b>.
+      </li>
     </ul>
     <p>
       <a name="themes" id="themes"></a>