Bug type

Regression (worked before, now fails)

Summary

see Additional information

Steps to reproduce

1

Expected behavior

1

Actual behavior

1

OpenClaw version

3.13

Operating system

mac 15.7.4 (24G517)

Install method

npm

Model

step 3.5 flash

Provider / routing chain

openrouter

Config file / key location

No response

Additional provider/model setup details

No response

Logs, screenshots, and evidence

Impact and severity

No response

Additional information

Title: [Control UI] Duplicate messages appear in chat when AI replies complete (intermittent)

Labels: bug, priority:p2, area:control-ui, area:chat, regression

Description

When using the Control UI (dashboard v2), assistant messages are sometimes displayed twice in the chat view after an AI reply completes. The duplication is intermittent — it doesn't happen on every reply, but appears randomly under certain network conditions.

Observed Behavior

• After the assistant finishes a response, the same message sometimes appears two times in the chat history view.
• The duplication is not immediate in all cases; sometimes the second copy appears shortly after the first.
• Refreshing the page (Cmd+R) clears the duplication and restores the correct single-message view.
• The issue does not appear on every reply — it is intermittent.

Verification: Backend Is Not at Fault

I inspected the session log file (.openclaw/agents/main/sessions/<session-id>.jsonl) and confirmed that backend storage is correct — each message is stored exactly once. The duplication happens only in the Control UI frontend rendering.

Likely Trigger

The duplication seems to occur when the gateway re-transmits the same final event (e.g., due to network jitter, WebSocket reconnection, or reliability retry). The Control UI processes the first final event correctly, but if a duplicate final event with the same runId arrives later, it adds the same message again.

Code Location

The bug is in the Control UI's chat event handler, function gh() (in the bundled control-ui/assets/index-*.js), which processes chat events:

function gh(e, t) {
  // ...
  if (t.runId && e.chatRunId && t.runId !== e.chatRunId) {
    // Different runId — ignore (this protects against cross-run contamination)
    return null;
  }
  // t.state === 'final' → add message to e.chatMessages
  // e.chatRunId is then cleared (set to null)
}

Problem: After the first final event, e.chatRunId is set to null. When a duplicate final event with the same runId arrives later, the condition t.runId && e.chatRunId fails because e.chatRunId is null. The duplicate is not rejected and gets added again.

Temporary Workarounds

1. Refresh the page (Cmd+R) — reloads full history from backend, which is deduplicated.
2. Use /clear then re-fetch history (not ideal).

Proposed Fix

Track processed runId values separately from chatRunId. Example:

// In state initialization:
this.processedChatRunIds = new Set(); // or LRU cache with limit

// In gh():
if (t.runId && this.processedChatRunIds.has(t.runId)) {
  return null; // Already processed this runId
}

// After successfully handling final:
if (t.runId) {
  this.processedChatRunIds.add(t.runId);
  // Optional: prune size to avoid unbounded growth (keep last 100)
}

Alternatively, check for existing message content equality before adding, but runId tracking is simpler and more reliable.

Environment

• OpenClaw version: 2026.3.13 (from openclaw --version)
• Control UI: dashboard v2
• Browser: Chrome)
• Gateway: local