- ABI directory exists (template-level)
- No dangerous patterns
- Claims: safety ratings for 105+ Firefox flags, rollback protection
- Safety rating consistency: Prove the safety classification (Safe/Moderate/Advanced/Experimental) is consistent — no flag rated "Safe" that modifies security-relevant settings
- Rollback correctness: Prove that rollback restores the exact previous flag state (no partial rollback, no stale values)
- Flag conflict detection: Prove that enabling conflicting flags is detected and reported (no silent undefined behavior from flag combinations)
- Idris2 — Small enough domain that a complete flag-property model is feasible
- LOW — FireFlag is a browser extension with safety ratings. The risk is user confusion rather than data loss. Proofs would increase credibility but are not urgently needed.