[2FA] Set correct name for phone devices

aleksis/core/views.py

@@ -1521,6 +1521,16 @@ class TwoFactorSetupView(two_factor_views.SetupView):
     def get(self, request, *args, **kwargs):
         return super(two_factor_views.SetupView, self).get(request, *args, **kwargs)
 
+    def get_device(self, **kwargs):
+        device = super().get_device(**kwargs)
+
+        # Ensure that the device is named "backup" if it is a phone device
+        # to ensure compatibility with django_two_factor_auth
+        method = self.get_method()
+        if device and method.code in ("call", "sms"):
+            device.name = "backup"
+        return device
+
 
 class TwoFactorLoginView(two_factor_views.LoginView):
     def get_devices(self):