Auth0 login with redirect internal error with custom template

Hello!

I’ve been trying to set up Auth0 authorization using the Universal Login flow in Flutter Web. So far I’ve been successful to the point where I’m able to authorize without any issues, unless I customize the login page template (via a Management API request).
The documentation and other community questions suggest that additional configuration is required for it in order to work (e.g. Configure Features to Use Custom Domains).

Could you confirm that AuthLock configuration is necessary when a custom template is being used? It’s not clear whether this requirement applies to a situation updating the template via the api or just the web interface.

If the above is true, what would be the recommended way to do so in Flutter? The auth0_flutter doesn’t seem to provide an api to specify the additional configuration options.

The error that I get on the Flutter side in console:

══╡ EXCEPTION CAUGHT BY FLUTTER FRAMEWORK ╞═════════════════════════════════════════════════════════
js_primitives.dart:30 The following UnhandledActionError was thrown:
js_primitives.dart:30 server_error: Internal error
js_primitives.dart:30 
js_primitives.dart:30 When the exception was thrown, this was the stack:
js_primitives.dart:30 dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/errors.dart 297:3  throw_
js_primitives.dart:30 packages/auth0_flutter/src/web/auth0_flutter_plugin_real.dart 41:9           initialize
js_primitives.dart:30 dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 60:31           <fn>
js_primitives.dart:30 dart-sdk/lib/async/zone.dart 1423:47                                         _rootRunBinary
js_primitives.dart:30 dart-sdk/lib/async/zone.dart 1315:19                                         runBinary
js_primitives.dart:30 dart-sdk/lib/async/future_impl.dart 177:22                                   handleError
js_primitives.dart:30 dart-sdk/lib/async/future_impl.dart 850:46                                   handleError
js_primitives.dart:30 dart-sdk/lib/async/future_impl.dart 871:13                                   _propagateToListeners
js_primitives.dart:30 dart-sdk/lib/async/future_impl.dart 651:5                                    [_completeError]
js_primitives.dart:30 dart-sdk/lib/async/future_impl.dart 737:7                                    <fn>
js_primitives.dart:30 dart-sdk/lib/async/zone.dart 1399:13                                         _rootRun
js_primitives.dart:30 dart-sdk/lib/async/zone.dart 1301:19                                         run
js_primitives.dart:30 dart-sdk/lib/async/zone.dart 1209:7                                          runGuarded
js_primitives.dart:30 dart-sdk/lib/async/zone.dart 1249:23                                         callback
js_primitives.dart:30 dart-sdk/lib/async/schedule_microtask.dart 40:11                             _microtaskLoop
js_primitives.dart:30 dart-sdk/lib/async/schedule_microtask.dart 49:5                              _startMicrotaskLoop
js_primitives.dart:30 dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 181:7           <fn>
js_primitives.dart:30 ════════════════════════════════════════════════════════════════════════════════════════════════════

and a corresponding Dart error:

WebException (server_error: Internal error)
  code: "server_error"
  details: Map (2 items)
    0: "state" -> "UEhPUDVOVDZ2SWFIbGpOaExnUzdTdmhiWTV4NS55LUpLMDdwZmRTQ0pqQw=="
    1: "appState" -> null
  hashCode: 261623223
  message: "Internal error"
  runtimeType: Type (WebException)