As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RETURNED, ACFT WAS GNDED. SHORTLY AFTER REACHING FL390 FIRST OFFICERS WINDSHIELD STARTING ARCING. THE FLIGHT CREW PULLED W14 CB IAW QRH PROCEDURE, DECLARED AN EMER & RETURNED WHERE THE ACFT LANDED SAFELY WITH NO FURTHER INCIDENT. REPLACED THE NR 2 WINDOW HEAT COMPUTER & THE FIRST OFFICERS WINDSHIELD IAW AMM 30-42-34 & 56-11-11. A SATISFACTORY OPERATIONAL CHECK WAS ACCOMPLISHED. SEE AALA 201605249001 FOR ADDITIONAL PART.