Note that the dev server is running in WSGI mode

[Matthew Pava]

With the mass adoption of async Django on the way, we need to provide a clearer warning in the development server that it is running in WSGI mode and not ASGI mode. I spent an hour troubleshooting a warning because I created a middleware that was async only. Only when I made it compatible for both async and sync modes did the warning go away.

Or we could just make the Django dev server default to ASGI mode.

Actual result:
The Django server displays this warning:
WARNING: This is a development server. Do not use it in a production setting. Use a production WSGI or ASGI server instead.
For more information on production servers see: ​https://docs.djangoproject.com/en/6.0/howto/deployment/

Desired result:
Revise it to something like:
WARNING: This is a development server that is running only in sync mode (WSGI). Only middleware that is compatible with sync mode (WSGI) will run properly. Do not use it in a production setting. Use a production WSGI or ASGI server instead.