As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SEA/PHL - FLT 110 - EN ROUTE, THE FIRST OFFICER'S SLIDING WINDOW CRACKED. A RAPID DESCENT WAS INITIATED TO 10,000 FEET TO RELIEVE PRESSURE ON THE WINDOW. THE AIRCRAFT LANDED AT THE DESTINATION WITHOUT INCIDENT. MAINTENANCE REPLACED THE FIRST OFFICER'S SLIDING WINDOW ASSEMBLY. (X)