As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: AT CRUISE FL 370 FIRST OFFICERÏ¿½S SIDE WINDOW CRACKED. NO ARCING OBSERVED, CO-ORDINATED WITH MAINTENANCE, DESCENDED TO FL 250 TO RELIEVE DIFFERENTIAL PRESSURE. EMERGENCY DECLARED; FLIGHT LANDED SAFELY AT LHR. MAINTENANCE REPLACED FIRST OFFICERÏ¿½S #2 WINDOW PER JOB CARD (AALA202306266440) AND REPLACED WINDOW HEART PROTECTION UNIT PER AMM 30-41-03 (AALA202306261470). ACCOMPLISHED SATISFACTORY OPERATIONAL CHECK.