As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CAPTAIN SIDE O2 MASK BROKEN. HARNESS FEELS LIKE IT SNAPPED. SWAPPED CAPT O2 MASK WITH OBSV MASK. DEFERRED OBSV SEAT IAW MEL 35-10-1. REMOVED AND REPLACED OBSERVER O2 MASK IAW 35-11-12 PERFORMED LEAK TEST. OPS TEST PF THE CREW O2 AND OPS TEST OF THE OBSERVER O2 MICROPHONE IAW 35-10-00 AND 23-51-00.