From CNA:
On Wednesday, Oct. 2, the Holy Father had the opportunity to view the historic relic of St. Peter’s chair in the Ottoboni sacristy of St. Peter’s Basilica after celebrating Mass in St. Peter’s Square ahead of the second session of the Synod on Synodality. The photo of him sitting before the chair went viral.
Francis is the first pope since 1974 to have viewed the relic believed to have belonged to St. Peter the Apostle.