Behind the scenes, we’re accelerating requests for Custom Domains by moving them to Salesforce Edge.
This move improves performance through machine learning. You don’t need to do anything for this
move. Keep using the same Custom Domain addresses for your Sites and Communities, and we’ll do the
rest.
https://help.salesforce.com/s/articleView?id=release-notes.rn_security_route_my_domain_edge_cruc.htm&release=226&type=5