As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS NOT GROUNDED: SMOKE IN MID LAVATORY ECAM MESSAGE FLASHED MOMENTARILY. CABIN CREW INSPECTION SHOWED NO SIGN OF FIRE OR SMOKE. MAINTENANCE INSPECTED SMOKE DETECTOR AND ACCOMPLISHED A SATISFACTORY OPERATIONAL CHECK OF THE SMOKE DETECTION SYSTEM WITH NO FAULTS OR ISSUES NOTED.