diff --git a/web/hwlab-cloud-web/src/components/conversation/ConversationPanel.test.ts b/web/hwlab-cloud-web/src/components/conversation/ConversationPanel.test.ts
index 8da11448..0a117d3b 100644
--- a/web/hwlab-cloud-web/src/components/conversation/ConversationPanel.test.ts
+++ b/web/hwlab-cloud-web/src/components/conversation/ConversationPanel.test.ts
@@ -52,10 +52,23 @@ test("conversation panel does not consume replay opportunity before timer fires"
   const effectStart = source.indexOf("const replayRequestedTraceRef = useRef<string | null>(null);");
   const timerStart = source.indexOf("const timer = window.setTimeout", effectStart);
   const markRequested = source.indexOf("replayRequestedTraceRef.current = traceId", effectStart);
-  const replayCall = source.indexOf("onReplayTrace();", effectStart);
+  const replayCall = source.indexOf("replayHandlerRef.current();", effectStart);
 
   assert.ok(effectStart > 0, "replay guard ref exists");
   assert.ok(timerStart > effectStart, "auto replay uses delayed timer");
   assert.ok(markRequested > timerStart, "route changes that cancel the timer must not mark replay as already requested");
   assert.ok(replayCall > markRequested, "replay is marked requested only immediately before dispatching replay");
 });
+
+test("conversation panel keeps replay timer stable across parent rerenders", async () => {
+  const source = await Bun.file(new URL("./ConversationPanel.tsx", import.meta.url)).text();
+  const handlerRef = source.indexOf("const replayHandlerRef = useRef(onReplayTrace);");
+  const effectStart = source.indexOf("const timer = window.setTimeout", handlerRef);
+  const effectEnd = source.indexOf("if (message.role === \"agent\")", effectStart);
+  const effectSource = source.slice(effectStart, effectEnd);
+
+  assert.ok(handlerRef > 0, "onReplayTrace is kept behind a stable ref");
+  assert.match(effectSource, /replayHandlerRef\.current\(\);/u);
+  assert.match(effectSource, /\}, \[shouldReplayTrace, traceId\]\);/u);
+  assert.doesNotMatch(effectSource, /\bonReplayTrace\b/u);
+});
diff --git a/web/hwlab-cloud-web/src/components/conversation/ConversationPanel.tsx b/web/hwlab-cloud-web/src/components/conversation/ConversationPanel.tsx
index 746d8fa7..9257e672 100644
--- a/web/hwlab-cloud-web/src/components/conversation/ConversationPanel.tsx
+++ b/web/hwlab-cloud-web/src/components/conversation/ConversationPanel.tsx
@@ -131,16 +131,21 @@ const HISTORICAL_TRACE_REPLAY_DELAY_MS = 4500;
 function MessageCard({ message, firstScreenHistory, codeAgentTimeoutMs, onCancel, onRetry, onReplayTrace }: { message: ChatMessage; firstScreenHistory: boolean; codeAgentTimeoutMs: number; onCancel(): void; onRetry(): void; onReplayTrace(): void }): ReactElement {
   const traceKey = `hwlab.workbench.trace-open.${message.traceId ?? message.id}`;
   const replayRequestedTraceRef = useRef<string | null>(null);
+  const replayHandlerRef = useRef(onReplayTrace);
+  useEffect(() => {
+    replayHandlerRef.current = onReplayTrace;
+  }, [onReplayTrace]);
+  const traceId = message.traceId ?? message.runnerTrace?.traceId ?? null;
+  const shouldReplayTrace = shouldAutoReplayTrace(message);
   useEffect(() => {
-    const traceId = message.traceId ?? message.runnerTrace?.traceId ?? null;
     if (traceId && replayRequestedTraceRef.current === traceId) return;
-    if (!shouldAutoReplayTrace(message)) return;
+    if (!shouldReplayTrace) return;
     const timer = window.setTimeout(() => {
       replayRequestedTraceRef.current = traceId;
-      onReplayTrace();
+      replayHandlerRef.current();
     }, HISTORICAL_TRACE_REPLAY_DELAY_MS);
     return () => window.clearTimeout(timer);
-  }, [message, onReplayTrace]);
+  }, [shouldReplayTrace, traceId]);
   if (message.role === "agent") {
     const hasFinalResponse = message.status !== "running" && message.text.trim().length > 0;
     return (