Override strong params for sign up.

app/controllers/application_controller.rb

@@ -247,7 +247,6 @@ class ApplicationController < ActionController::Base
 
   def configure_permitted_parameters
     devise_parameter_sanitizer.sanitize(:sign_in) { |u| u.permit(:username, :email, :password, :login, :remember_me) }
-    devise_parameter_sanitizer.sanitize(:sign_up) { |u| u.permit(:username, :email, :name, :password, :password_confirmation) }
   end
 
   def hexdigest(string)

app/controllers/registrations_controller.rb

@@ -28,4 +28,8 @@ class RegistrationsController < Devise::RegistrationsController
   def signup_enabled?
     redirect_to new_user_session_path unless Gitlab.config.gitlab.signup_enabled
   end
+
+  def sign_up_params
+    params.require(:user).permit(:username, :email, :name, :password, :password_confirmation)
+  end
 end