As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS NOT GROUNDED: AT FL340 IN CRUISE ECAM SMOKE LAVATORY SMOKE MASTER CAUTION FO R3 SECONDS THEN CLEARED ITSELF - THE FLIGHT ATTENDANTS REPORTED NO ISSUES IN ANY OF THE LAVATORIES - MAINTENANCE ACCOMPLISHED A SATISFACTORY OPERATIONAL CHECK PER AMM 26-17-00 WITH NO FAULTS NOTED