ConnectionAbortedError/asyncio.CancelledError when the page's loading is canceled by the user is not catchable. #230

The error ConnectionAbortedError is thrown if the page's loading is canceled. Using @app.errorhandler(ConnectionAbortedError) with an appropriate function is completely ignored. How do I handle (or just suppress) this error?

reproducible example:

from quart import Quart
from time import sleep
import asyncio

app = Quart(__name__)

@app.route('/')
async def hello():
    await asyncio.sleep(1)
    return 'Hello, world!'

if __name__ == '__main__':
    app.run()

reproduce the bug:
run the script. connect to localhost:5000. cancel the load when the page is loading.

traceback: https://pastebin.com/aueksHyg

this error should not be thrown (or there needs to be a way to catch it.)

Environment:

• Python version: 3.11.2
• Quart version: 0.18.4