httpx.ReadError happens for some websites without actual reason!

[AmericanY]

import trio
import httpx

proxies = {
    "all://": "http://127.0.0.1:8866"
}


async def main():
    async with httpx.AsyncClient(timeout=None, proxies=proxies, verify=False) as client:
        r = await client.get('https://cndt-certidao.tst.jus.br/inicio.faces')
        print(r)

if __name__ == "__main__":
    trio.run(main)

The proxy is being used is ref. to Fiddler

Traceback (most recent call last):
  File "C:\Users\AmericaN\Desktop\Lab\MyEnv\lib\site-packages\httpx\_transports\default.py", line 61, in map_httpcore_exceptions
    yield
  File "C:\Users\AmericaN\Desktop\Lab\MyEnv\lib\site-packages\httpx\_transports\default.py", line 203, in __aiter__
    async for part in self._httpcore_stream:
  File "C:\Users\AmericaN\Desktop\Lab\MyEnv\lib\site-packages\httpcore\_async\connection_pool.py", line 57, in __aiter__
    async for chunk in self.stream:
  File "C:\Users\AmericaN\Desktop\Lab\MyEnv\lib\site-packages\httpcore\_bytestreams.py", line 91, in __aiter__
    async for chunk in self._aiterator:
  File "C:\Users\AmericaN\Desktop\Lab\MyEnv\lib\site-packages\httpcore\_async\http11.py", line 208, in _receive_response_data
    event = await self._receive_event(timeout)
  File "C:\Users\AmericaN\Desktop\Lab\MyEnv\lib\site-packages\httpcore\_async\http11.py", line 225, in _receive_event
    data = await self.socket.read(self.READ_NUM_BYTES, timeout)
  File "C:\Users\AmericaN\Desktop\Lab\MyEnv\lib\site-packages\httpcore\_backends\trio.py", line 66, in read
    raise exc
  File "C:\Program Files\Python39\lib\contextlib.py", line 135, in __exit__    
    self.gen.throw(type, value, traceback)
  File "C:\Users\AmericaN\Desktop\Lab\MyEnv\lib\site-packages\httpcore\_exceptions.py", line 12, in map_exceptions
    raise to_exc(exc) from None
httpcore.ReadError

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "c:\Users\AmericaN\Desktop\Lab\ccap.py", line 16, in <module>
    trio.run(main)
  File "C:\Users\AmericaN\Desktop\Lab\MyEnv\lib\site-packages\trio\_core\_run.py", line 1932, in run
    raise runner.main_task_outcome.error
  File "c:\Users\AmericaN\Desktop\Lab\ccap.py", line 12, in main
    r = await client.get('https://cndt-certidao.tst.jus.br/inicio.faces')
  File "C:\Users\AmericaN\Desktop\Lab\MyEnv\lib\site-packages\httpx\_client.py", line 1722, in get
    return await self.request(
  File "C:\Users\AmericaN\Desktop\Lab\MyEnv\lib\site-packages\httpx\_client.py", line 1481, in request
    response = await self.send(
  File "C:\Users\AmericaN\Desktop\Lab\MyEnv\lib\site-packages\httpx\_client.py", line 1586, in send
    raise exc
  File "C:\Users\AmericaN\Desktop\Lab\MyEnv\lib\site-packages\httpx\_client.py", line 1577, in send
    await response.aread()
  File "C:\Users\AmericaN\Desktop\Lab\MyEnv\lib\site-packages\httpx\_models.py", line 1561, in aread
    self._content = b"".join([part async for part in self.aiter_bytes()])
  File "C:\Users\AmericaN\Desktop\Lab\MyEnv\lib\site-packages\httpx\_models.py", line 1561, in <listcomp>
    self._content = b"".join([part async for part in self.aiter_bytes()])
  File "C:\Users\AmericaN\Desktop\Lab\MyEnv\lib\site-packages\httpx\_models.py", line 1577, in aiter_bytes
    async for raw_bytes in self.aiter_raw():
  File "C:\Users\AmericaN\Desktop\Lab\MyEnv\lib\site-packages\httpx\_models.py", line 1631, in aiter_raw
    async for raw_stream_bytes in self.stream:
  File "C:\Users\AmericaN\Desktop\Lab\MyEnv\lib\site-packages\httpx\_client.py", line 150, in __aiter__
    async for chunk in self._stream:
  File "C:\Users\AmericaN\Desktop\Lab\MyEnv\lib\site-packages\httpx\_transports\default.py", line 204, in __aiter__
    yield part
  File "C:\Program Files\Python39\lib\contextlib.py", line 135, in __exit__
    self.gen.throw(type, value, traceback)
  File "C:\Users\AmericaN\Desktop\Lab\MyEnv\lib\site-packages\httpx\_transports\default.py", line 78, in map_httpcore_exceptions
    raise mapped_exc(message) from exc
httpx.ReadError