- Improved logging for invalid ``Host`` headers. This was previously logged as an uncaught
exception with a stack trace, now it is simply a 400 response (logged as a warning in the
access log).
-- Restored the ``host`` argument to ``.HTTPServerRequest``. This argument is deprecated
+- Restored the ``host`` argument to `.HTTPServerRequest`. This argument is deprecated
and will be removed in the future, but its removal with no warning in 6.5.0 was a mistake.
- Removed a debugging print statement that was left in the code.
- Improved type hints for ``gen.multi``.
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