As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BUTTON LEFT WINDOW HEATER (CPT SIDE FRONT WINDOW) SPARKED AND THEN SMOKE FOLLOWED. I TURNED OFF BOTH IMMEDIATELY FOR THE REMAINDER OF THE FLIGHT. (FLIGHT 4048 - FILED CLOSED) COMPLIED WITH RIL 11891 REV. A. DEFERRED LH WINDOW HEAT PER MEL 30-41-1A. PULLED AND COLLARED CB'S A10, A11, AND G12. MX ACTIONS COMPLIED WITH, PLACARD INSTALLED.