make guide consistent for 1.5.1 changes

src/OEBPS/Text/user_interface.xhtml

@@ -222,7 +222,7 @@
     <li><span class="listheading">Remove Tag Pair:</span> Remove open and close tag (place the cursor inside the tag to select it).</li>
   </ul>
   <div class="tip">
-    <p class="tip">Users can double-click in a tag to select just that tag’s contents. Or use shift double-click in a tag to select that tag and its contents. This can be useful for using <b>Remove Formatting</b></p>
+    <p class="tip">Users can shift double-click in a tag to select just that tag’s contents. Or use alt double-click in a tag to select that tag and its contents. This can be useful for using <b>Remove Formatting</b></p>
   </div>
   <p class="heading">Search</p>
 
@@ -816,4 +816,4 @@
     <p class="tiptext">There are many tooltips available in Sigil. Most dialogs and buttons will provide some help text.</p>
   </div>
 </body>
-</html>
+</html>