HTTPSMiddleware not responding for HTTP [_ProactorBasePipeTransport._call_connection_lost(None)]

[drcdr]

I'm trying to get https redirect working with FastAPI (and loosely following the approach here). I have narrowed my problem down to a Starlette-only configuration.

I'm using conda and Windows 10. I created a new environment:

conda create -n uvistd python=3.11
conda activate uvistd
pip install uvicorn[standard] starlette

This results in uvicorn 0.26.0 and starlette 0.35.1.
My example:

import uvicorn
from starlette.applications import Starlette
from starlette.responses import PlainTextResponse
from starlette.middleware import Middleware
from starlette.middleware.httpsredirect import HTTPSRedirectMiddleware
from starlette.routing import Route

async def message(request):
    return PlainTextResponse('Message')

routes = [ Route("/get_message", endpoint=message), ]

middleware = [ Middleware(HTTPSRedirectMiddleware) ]
app = Starlette(routes=routes, middleware=middleware)
uvicorn.run(app, host='127.0.0.1', port=443,
            ssl_keyfile='./certs/key.pem', ssl_certfile='./certs/cert.pem')

I run as python test_starlette.py
Using https://127.0.0.1/get_message works as expected.
When I try http://127.0.0.1:80/get_message, I get a 404 error:
No webpage was found for the web address: http://127.0.0.1/get_message
When I try http://127.0.0.1/get_message, I get an ERR_EMPTY_RESPONSE on the page, and this error in the logs:

Exception in callback _ProactorBasePipeTransport._call_connection_lost(None)
handle: <Handle _ProactorBasePipeTransport._call_connection_lost(None)>
Traceback (most recent call last):
  File "C:\Dev\Anaconda3\envs\uvistd\Lib\asyncio\events.py", line 80, in _run
    self._context.run(self._callback, *self._args)
  File "C:\Dev\Anaconda3\envs\uvistd\Lib\asyncio\proactor_events.py", line 165, in _call_connection_lost
    self._sock.shutdown(socket.SHUT_RDWR)
ConnectionResetError: [WinError 10054] An existing connection was forcibly closed by the remote host

I've tried several different things, all of which give similar results as above

• changing the port to something like 8060 (https://127.0.0.1:8060/get_message works, http://127.0.0.1:8060/get_message doesn't, same ERR_EMPTY_RESPONSE and crash)
• my own version of the HTTPSRedirectMiddleware, lightly modified so I can debug easier; it never reaches the redirect code
• using uvicorn instead of uvicorn[std]
• adding Middleware(CORSMiddleware, allow_origins=["*"], allow_credentials=True, allow_methods=["*"], allow_headers=["*"] ), both before and after HTTPSRedirectMiddleware

WSL2: I've tried everything above in WSL2 as well, modifying the port from 443 to 8000 so I don't have to run as root. I don't get the asyncio trace error, but I also don't get the http redirect to work (still ERR_EMPTY_RESPONSE on http, port 8000).

I'm not exactly sure how this redirect is supposed to work (from reading discussions at starlette, and various web posts), as far as scheme and port substitution, so I'm posting here before posting a bug. Thanks!