As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BEHIND FIRST CLASS SEATS 3AB. A PUFF OF SMOKE NOTED IN CABIN VISUALLY WITH ELECT SMELL PERFORMED FORM 46-6020 AND INSPECTION AND CHECK IAW 05-51-10-200 -801C1. INSPECTED AREA AND FOUND NO ELECTRICAL ISSUES WITH ANY OF THE SEAT ELEC UNITS. CHECK ALL CONNECTIONS. THERE WAS NO SMELL OF ELEC ISSUES. MIGHT HAVE BEEN A PERSONAL ECEL. DEVICE BROUGHT ON BY THE PASSENGER. OK FOR SERVICE.