Return only the first 100 pinned messages

src/hooks/usePinnedEvents.ts

@@ -27,16 +27,18 @@ import PinningUtils from "../utils/PinningUtils";
 
 /**
  * Get the pinned event IDs from a room.
+ * The number of pinned events is limited to 100.
  * @param room
  */
 function getPinnedEventIds(room?: Room): string[] {
-    return (
+    const eventIds: string[] =
         room
             ?.getLiveTimeline()
             .getState(EventTimeline.FORWARDS)
             ?.getStateEvents(EventType.RoomPinnedEvents, "")
-            ?.getContent()?.pinned ?? []
-    );
+            ?.getContent()?.pinned ?? [];
+    // Limit the number of pinned events to 100
+    return eventIds.slice(0, 100);
 }
 
 /**

test/components/views/right_panel/PinnedMessagesCard-test.tsx

@@ -196,6 +196,21 @@ describe("<PinnedMessagesCard />", () => {
         expect(asFragment()).toMatchSnapshot();
     });
 
+    it("should not show more than 100 messages", async () => {
+        const events = Array.from({ length: 120 }, (_, i) =>
+            mkMessage({
+                event: true,
+                room: "!room:example.org",
+                user: "@alice:example.org",
+                msg: `The message ${i}`,
+                ts: i,
+            }),
+        );
+        await initPinnedMessagesCard(events, []);
+
+        expect(screen.queryAllByRole("listitem")).toHaveLength(100);
+    });
+
     it("should updates when messages are pinned", async () => {
         // Start with nothing pinned
         const { addLocalPinEvent, addNonLocalPinEvent } = await initPinnedMessagesCard([], []);