Enable CDN to Load Lightning Experience Faster
Where: This setting affects Lightning Experience and other apps that are built on the Lightning Component framework. This setting doesn't affect any version of the Salesforce app. This setting doesn’t affect Lightning communities.
How: This setting is disabled by default for existing orgs and enabled by default for new orgs.
To enable CDN, from Setup, enter Session in the Quick Find box, and then select Session Settings. Select Enable Content Delivery Network (CDN) for Lightning Component framework, and click Save.
If you experience issues, ask your IT department if your company’s firewall blocks Akamai CDN content.