New GitHub issue #100991 from mricon:<br>

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<pre>
# Bug report

```python
import email
import email.policy

msg = email.message.EmailMessage()
msg['Message-Id'] = '<long-but-perfectly-valid-message-id-that-does-not-end-up-qp-encoded@example.com>'
msg['References'] = '<reference-to-long-but-perfectly-valid-message-id-that-gets-qp-encoded@example.com>'
msg['In-Reply-To'] = '<reference-to-long-but-perfectly-valid-message-id-that-gets-qp-encoded@example.com>'
msg.set_payload('No body')

bdata = msg.as_bytes(policy=email.policy.SMTP)
print(bdata.decode())
```

Expected output:

```
Message-Id: <long-but-perfectly-valid-message-id-that-does-not-end-up-qp-encoded@example.com>
References: <reference-to-long-but-perfectly-valid-message-id-that-gets-qp-encoded@example.com>
In-Reply-To: <reference-to-long-but-perfectly-valid-message-id-that-gets-qp-encoded@example.com>

No body
```

Actual output:

```
Message-Id: <long-but-perfectly-valid-message-id-that-does-not-end-up-qp-encoded@example.com>
References: <reference-to-long-but-perfectly-valid-message-id-th
 at-gets-qp-encoded@example.com>
In-Reply-To: <reference-to-long-but-perfectly-valid-message-id-t
 hat-gets-qp-encoded@example.com>

No body
```

# Your environment

- CPython versions tested on: 3.11.1
- Operating system and architecture: Fedora 37 x86_64

</pre>

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<a href="https://github.com/python/cpython/issues/100991">View on GitHub</a>
<p>Labels: type-bug</p>
<p>Assignee: </p>