diff --git a/calendar/templates/default/app.css b/calendar/templates/default/app.css
index 6e882be6d4..14dcc380b5 100644
--- a/calendar/templates/default/app.css
+++ b/calendar/templates/default/app.css
@@ -201,6 +201,7 @@ e.g. the div with class calTimeGrid is generated by the timeGridWidget method of
 	border-width: 1px;
 	border-radius: 6px;
 	-moz-border-radius: 6px;
+	-webkit-border-radius: 6px;
 /* set via inline style on runtime:
  *  top: depending on startime
  *  height: depending on length
@@ -239,6 +240,7 @@ e.g. the div with class calTimeGrid is generated by the timeGridWidget method of
 .calEventTooltip{
 	border-radius: 6px;
 	-moz-border-radius: 6px;
+	-webkit-border-radius: 6px;
 	max-height: 400px;
 	overflow: auto;
 }