Internal server error: split

[JerumanSama]

Internal Error Stacktrace:

Error Message: 'NoneType' object has no attribute 'split'

Traceback (most recent call last):
  File "/opt/hiddify-manager/.venv313/lib/python3.13/site-packages/flask/app.py", line 917, in full_dispatch_request
    rv = self.dispatch_request()
  File "/opt/hiddify-manager/.venv313/lib/python3.13/site-packages/flask/app.py", line 902, in dispatch_request
    return self.ensure_sync(self.view_functions[rule.endpoint])(**view_args)  # type: ignore[no-any-return]
  File "/opt/hiddify-manager/.venv313/lib/python3.13/site-packages/flask_classful.py", line 303, in proxy
    response = view(**request.view_args)
  File "/opt/hiddify-manager/.venv313/lib/python3.13/site-packages/flask_classful.py", line 271, in inner
    return fn(*args, **kwargs)
  File "/opt/hiddify-manager/.venv313/lib/python3.13/site-packages/hiddifypanel/auth.py", line 130, in decorated_view
    return fn(*args, **kwargs)
  File "/opt/hiddify-manager/.venv313/lib/python3.13/site-packages/apiflask/scaffold.py", line 41, in wrapper
    return current_app.ensure_sync(f)(*args, **kwargs)
  File "/opt/hiddify-manager/.venv313/lib/python3.13/site-packages/hiddifypanel/panel/user/user.py", line 91, in singbox_full
    return self.full_singbox_imp()
  File "/opt/hiddify-manager/.venv313/lib/python3.13/site-packages/hiddifypanel/auth.py", line 130, in decorated_view
    return fn(*args, **kwargs)
  File "/opt/hiddify-manager/.venv313/lib/python3.13/site-packages/apiflask/scaffold.py", line 41, in wrapper
    return current_app.ensure_sync(f)(*args, **kwargs)
  File "/opt/hiddify-manager/.venv313/lib/python3.13/site-packages/hiddifypanel/panel/user/user.py", line 264, in full_singbox_imp
    link_res=get_and_merge_urls(hconfig(ConfigEnum.additional_configs_urls).split("\n"))

Details:

Hiddify Version: 12.1.0b5
Python Version: 3.13.4 (main, Jun 4 2025, 17:37:06) [Clang 20.1.4 ]
OS: Linux-5.15.0-171-generic-x86_64-with-glibc2.35
User Agent: Unknown