diff --git a/calendar/base/content/widgets/calendar-item-summary.js b/calendar/base/content/widgets/calendar-item-summary.js
index 3bdaf9350a..f1fe136a2d 100644
--- a/calendar/base/content/widgets/calendar-item-summary.js
+++ b/calendar/base/content/widgets/calendar-item-summary.js
@@ -481,7 +481,7 @@
         this.updateStatus(status, isToDoItem);
       }
 
-      let description = item.getProperty("DESCRIPTION");
+      let description = item.getProperty("DESCRIPTION")?.trim();
       if (description) {
         this.updateDescription(description);
       }