What are Enhanced Domains in Salesforce and why are they important?

Enhanced Domains is Salesforce's updated URL format that includes the My Domain name in all Salesforce URLs (Experience Cloud sites, Visualforce pages, content files). Format: orgname.sandbox.my.salesforce.com instead of the older c.na1.visual.force.com. Benefits:

1. Improves security by ensuring all content is served from the org's domain, blocking cross-org cookie access.
2. Enables stricter browser security policies.
3. Required for Salesforce to meet evolving browser security standards.
4. Simplifies CSP (Content Security Policy) configuration. Enhanced Domains became mandatory as of Spring '23. Admins must update any hardcoded URLs in integrations, email templates, or external systems that reference old domain formats after enabling Enhanced Domains.