--- a/src/pyams_zodbbrowser/zmi/templates/zodbhistory.pt	Tue May 16 11:41:47 2017 +0200
+++ b/src/pyams_zodbbrowser/zmi/templates/zodbhistory.pt	Mon May 22 00:46:01 2017 +0200
@@ -42,7 +42,7 @@
 			</h4>
 
 			<div class="diff">
-				<h5 class="expander">
+				<h5 class="expander" data-ams-click-handler="PyAMS_zodbbrowser.collapseOrExpand">
 					<img src="/--static--/pyams_zodbbrowser/img/collapse.png"
 						 alt="collapse"
 							tal:condition="not:history.hidden"