As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MAIN AVIONICS BAY STR 21R CORRODED BETWEEN FS319.70 AND FS333.00 (C-CHECK) RO 3/4/2021 REPLACED STRINGER 21R, FS280.00-FS333.00 REF CRJ-900 SRM 51-42-06-001-00-A01, SRM 51-42-21-001-001-A01 & DRAWING SH670-31630 REV K. SEE CONTINUATION CARD FOR DETAILS. CHECKS GOOD. COMPLIED WITH TASK CARD 51-900-1002-SKY.