As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PASSENGER AT 27B HAD PHONE CHARGER PLUGGED INTO RECEPTACLE 27B, THE PHONE CHARGER BECAME HOT. PASSENGER UNPLUGGED THE CHARGER AND A SMALL SPARK OCCURRED. CAPTAIN TURNED OFF SEAT POWER AND RETURNED TO GATE. GROUNDED - YES. REMOVED AND REPLACED SEAT 27B ACOU PER AMM 44-60-00 OPS CHECK NORMAL.