Various fixes (#20655)

web/src/components/card/ClassificationCard.tsx

@@ -214,7 +214,9 @@ export function GroupedClassificationCard({
     });
 
     if (!best) {
-      return group.at(-1);
+      // select an item from the middle of the time series as this usually correlates
+      // to a more representative image than the first or last
+      return group.at(Math.floor(group.length / 2));
     }
 
     const bestTyped: ClassificationItemData = best;