diff --git a/calendar/templates/default/app.css b/calendar/templates/default/app.css
index 5b5bd804a2..1242173028 100644
--- a/calendar/templates/default/app.css
+++ b/calendar/templates/default/app.css
@@ -462,7 +462,7 @@ e.g. the div with class calendar_calTimeGrid is generated by the timeGridWidget
 	display: inline-block;
 	white-space: nowrap;
 	/* This determines how many per line */
-	flex: 1 1 6ex;
+	flex: 1 1 20em;
 }
 .calendar_calEventTooltip{
 	border-radius: 6px;