openclaw - 💡(How to fix) Fix Webchat UI: Long streamed responses disappear after near-complete render

Bug description

Long responses rendered in the OpenClaw webchat UI disappear entirely after rendering almost completely. The underlying agent work completes correctly — tool calls succeed, files are written, crons are created — only the final rendered reply is lost from the UI.

Steps to reproduce

1. Agent generates a long response (100–200+ lines, typically containing markdown tables or structured output)
2. Response streams and renders to near-completion in webchat
3. Response disappears entirely — blank state, no error shown
4. Refreshing the UI does not restore the response
5. Work completed by the agent is unaffected

Expected behaviour

Completed response remains visible in the UI

Actual behaviour

Response disappears entirely after streaming to near-completion

Session details

• Agent: main
• Date: 2026-06-01
• Occurrences: 4x at approx 10:17, 10:40, 10:43, 10:52 AEST
• OpenClaw version: 2026.5.28
• Platform: macOS

Hypothesis

Likely a race condition or DOM wipe triggered on long streamed responses. Possible correlations:

• Response length threshold
• Markdown table rendering completing before stream closes
• Stream completion event triggering a UI state reset

Impact

Work is not lost but user has no visibility of the response. For autonomous agent setups this means confirmations are invisible until the user re-prompts.

Workaround

Ask the agent to resend a summary after any long response.

Notes

This started occurring on 2026-06-01 after updating to v2026.5.28. Did not occur on prior versions.