1 files changed, 12 insertions, 0 deletions
diff --git a/synapse/config/registration.py b/synapse/config/registration.py
index 7a059c6dec..ea9b50fe97 100644
--- a/synapse/config/registration.py
+++ b/synapse/config/registration.py
@@ -190,6 +190,8 @@ class RegistrationConfig(Config):
         # The success template used during fallback auth.
         self.fallback_success_template = self.read_template("auth_success.html")
 
+        self.inhibit_user_in_use_error = config.get("inhibit_user_in_use_error", False)
+
     def generate_config_section(self, generate_secrets=False, **kwargs):
         if generate_secrets:
             registration_shared_secret = 'registration_shared_secret: "%s"' % (
@@ -446,6 +448,16 @@ class RegistrationConfig(Config):
         # Defaults to true.
         #
         #auto_join_rooms_for_guests: false
+
+        # Whether to inhibit errors raised when registering a new account if the user ID
+        # already exists. If turned on, that requests to /register/available will always
+        # show a user ID as available, and Synapse won't raise an error when starting
+        # a registration with a user ID that already exists. However, Synapse will still
+        # raise an error if the registration completes and the username conflicts.
+        #
+        # Defaults to false.
+        #
+        #inhibit_user_in_use_error: true
         """
             % locals()
         )