Adopt Instanceless My Domain URL Best Practices

A critical update in Spring ’18 removed instance names from My Domain URLs. Update existing plug-in packages to support instanceless URLs before the critical update’s auto-activation date. Replace hard-coded references with relative URLs. Going forward, build packages that support both instance and instanceless URLs.

Where: This change applies to Lightning Experience and Salesforce Classic in Group, Professional, Enterprise, Performance, Unlimited, and Database.com editions.

When: The Remove Instance Names From URLs for Visualforce, Community Builder, Site.com Studio, and Content Files critical update will be activated in all orgs on March 16, 2019.