Whenever we anticipate an intentional breaking change, we update the Platform Roadmap and provide a migration to give developers the ability to upgrade and test their apps. Last week, we posted a reminder about our announcement to migrate and require all iframe apps on Facebook.com (Canvas Apps) to use POST by Saturday, March 12th.
With this migration, iframe apps on Facebook.com can no longer use preload FQL. Please note that preload FQL will continue to work for FBML apps and that the discontinued support of preload FQL for iframe apps does not impact FQL.
Please review our documentation and begin testing this migration by editing your app settings in the Developer App under the "Advanced" tab by selecting POST for Canvas migration.
On the 12th, the migration will be turned on for all apps for 5 minutes at 12pm PST, with increasing amounts of time each day thereafter. If you haven’t already migrated, this will most likely cause your app to break. We strongly encourage you to migrate as soon as possible or provide us with any questions/concerns below.