diff --git a/pixelegg/js/slider.js b/pixelegg/js/slider.js
index 8c284844d1..e2aedf242e 100644
--- a/pixelegg/js/slider.js
+++ b/pixelegg/js/slider.js
@@ -151,7 +151,7 @@ egw_LAB.wait(function() {
 	$j('#quick_add').on({
 		mouseover: function(ev){
 			// do NOT react on bubbeling events from contained selectbox
-			if (ev.relatedTarget.id != 'quick_add_selectbox')
+			if (ev.relatedTarget && ev.relatedTarget.id != 'quick_add_selectbox')
 			{
 				$j(this).css({
 					transition: "0.2s ease-out 0s",
@@ -168,7 +168,7 @@ egw_LAB.wait(function() {
 		},
 		mouseout: function(ev){
 			// do NOT react on bubbeling events from contained selectbox
-			if (ev.relatedTarget.id != 'quick_add_selectbox')
+			if (ev.relatedTarget && ev.relatedTarget.id != 'quick_add_selectbox')
 			{
 				$j(this).css({
 					transition: "0.2s ease-out 0s",