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app/models/application_setting.rb

@@ -660,6 +660,10 @@ class ApplicationSetting < ApplicationRecord
   Recursion = Class.new(RuntimeError)
 
   def self.create_from_defaults
+    # this is posssible if calls to create the record depend on application
+    # settings themselves. This was seen in the case of a feature flag called by
+    # `transaction` that ended up requiring application settings to determine metrics behavior.
+    # If something like that happens, we break the loop here, and let the caller decide how to manage it.
     raise Recursion if Thread.current[:application_setting_create_from_defaults]
 
     Thread.current[:application_setting_create_from_defaults] = true