In Winter ’22, Salesforce discontinued the Run Flows permission for the Guest User profile in new orgs. The change improves site security by requiring explicit guest user permissions to run flows. Without the Run Flows permission, you’re free to use the more granular permission structure embedded in Flows and give your users the detailed access they need. In Spring ’23, Salesforce removes Run Flows from the Guest User profile in all orgs. To avoid future access issues, we recommend updating your sites to the new permission structure before Spring ’23. This update was first available in Summer ’22.
Where: This change applies to Aura, LWR, and Visualforce sites accessed through Lightning Experience and Salesforce Classic in Enterprise, Performance, Unlimited, and Developer editions.
When: Salesforce enforces this update in Spring ’23. To get the major release upgrade date for your instance, go to Trust Status, search for your instance, and click the maintenance tab.
Require Granular Flow Permissions for Experience Cloud Guest Users (Release Update) (salesforce.com)