diff --git a/calendar/prototypes/themes/pinstripe/sun-calendar-event-dialog.css b/calendar/prototypes/themes/pinstripe/sun-calendar-event-dialog.css
index be6520cbef3..ec109481377 100644
--- a/calendar/prototypes/themes/pinstripe/sun-calendar-event-dialog.css
+++ b/calendar/prototypes/themes/pinstripe/sun-calendar-event-dialog.css
@@ -266,3 +266,11 @@ toolbar[iconsize="small"] .cal-toolbarbutton-2 {
 }
 #button-importance-high[disabled="true"] {
 }
+
+/*--------------------------------------------------------------------
+ *   Recurrence dialog preview border
+ *-------------------------------------------------------------------*/
+#preview-border {
+    border: none;
+    padding: 0px;
+}
diff --git a/calendar/prototypes/themes/winstripe/sun-calendar-event-dialog.css b/calendar/prototypes/themes/winstripe/sun-calendar-event-dialog.css
index fe0d37aa900..e102200d65c 100644
--- a/calendar/prototypes/themes/winstripe/sun-calendar-event-dialog.css
+++ b/calendar/prototypes/themes/winstripe/sun-calendar-event-dialog.css
@@ -264,3 +264,11 @@ toolbar[iconsize="small"] .cal-toolbarbutton-2 {
 }
 #button-importance-high[disabled="true"] {
 }
+
+/*--------------------------------------------------------------------
+ *   Recurrence dialog preview border
+ *-------------------------------------------------------------------*/
+#preview-border {
+    border: none;
+    padding: 0px;
+}
diff --git a/calendar/prototypes/wcap/sun-calendar-event-dialog-recurrence.xul b/calendar/prototypes/wcap/sun-calendar-event-dialog-recurrence.xul
index ebb802c557c..bde01abf502 100644
--- a/calendar/prototypes/wcap/sun-calendar-event-dialog-recurrence.xul
+++ b/calendar/prototypes/wcap/sun-calendar-event-dialog-recurrence.xul
@@ -516,10 +516,10 @@
   </groupbox>
 
   <!-- preview -->
-  <vbox id="recurrence-preview-box" flex="1">
+  <groupbox id="preview-border" flex="1">
     <label id="recurrence-preview-label"
            value="&event.recurrence.preview.label;"
            control="recurrence-preview"/>
     <recurrence-preview id="recurrence-preview" flex="1"/>
-  </vbox>
+  </groupbox>
 </dialog>