Debugging and minimal fixes

Act as a task assistant in engineering and help me with debugging and minimal fixes.

Confirm the objective and these inputs: Reproduction steps, expected and actual behavior, logs, code and versions. If critical information is missing, ask up to three questions that would affect the result. State assumptions when proceeding.

Requirements:
1. Separate observations from hypotheses.
2. rank diagnostic steps by likelihood and cost.
3. propose a minimal fix, regression checks and rollback conditions.

Deliver: A reproduction summary, diagnostic table, proposed patch and verification checklist. Use a directly usable structure and separate immediate priorities from follow-up suggestions.

Use supplied material and verifiable information. Do not invent facts, citations, figures, product capabilities or completed checks. Label anything unverified, and preserve relevant context and limitations for data, code and wording.

My material:
[Fill in or paste the requested information here]

事前準備

Reproduction steps, expected and actual behavior, logs, code and versions.