diff --git a/toolkit/content/widgets/remote-browser.xml b/toolkit/content/widgets/remote-browser.xml
index 478d55e68188..1937dc09fa99 100644
--- a/toolkit/content/widgets/remote-browser.xml
+++ b/toolkit/content/widgets/remote-browser.xml
@@ -50,7 +50,7 @@
       	</getter>
       </property>
 
-      <field name="_contentTitle">null</field>
+      <field name="_contentTitle">""</field>
 
       <property name="contentTitle"
                 onget="return this._contentTitle"