As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EN ROUTE SFO-DEN, CAPTAIN ADVISED DISPATCH OF ELECTRICAL SMELL AND LIGHT SMOKE COMING FROM LOWER LEFT HEATING UNIT ON WINDOW R3. SUSPECT INNER GLASS PANE CRACKED/SHATTERED DUE FROM ARCING. WINDOW (141T4004-22) RETURNED TO VENDOR FOR EVALUATION.