diff --git a/internal_packages/notifications/lib/sidebar/sync-activity.jsx b/internal_packages/notifications/lib/sidebar/sync-activity.jsx
index d413751bb..8a39c836e 100644
--- a/internal_packages/notifications/lib/sidebar/sync-activity.jsx
+++ b/internal_packages/notifications/lib/sidebar/sync-activity.jsx
@@ -83,7 +83,9 @@ export default class SyncActivity extends React.Component {
       'blink': this.state.blink,
     });
 
-    const ellipses = [1, 2, 3].map((i) => <span className={`ellipsis${i}`}>.</span>);
+    const ellipses = [1, 2, 3].map((i) => (
+      <span key={`ellipsis${i}`} className={`ellipsis${i}`}>.</span>)
+    );
 
     return (
       <div
diff --git a/internal_packages/notifications/lib/sidebar/syncback-activity.jsx b/internal_packages/notifications/lib/sidebar/syncback-activity.jsx
index a305f1190..88fac2eea 100644
--- a/internal_packages/notifications/lib/sidebar/syncback-activity.jsx
+++ b/internal_packages/notifications/lib/sidebar/syncback-activity.jsx
@@ -25,7 +25,9 @@ export default class SyncbackActivity extends React.Component {
       counts[label] += +task.numberOfImpactedItems()
     });
 
-    const ellipses = [1, 2, 3].map((i) => <span className={`ellipsis${i}`}>.</span>);
+    const ellipses = [1, 2, 3].map((i) => (
+      <span key={`ellipsis${i}`} className={`ellipsis${i}`}>.</span>)
+    );
 
     const items = _.pairs(counts).map(([label, count]) => {
       return (