Pluggy 1.4.0 was released a couple hours ago. It nows warns about old-style hook wrappers: https://github.com/matplotlib/pytest-mpl/blob/db0ea3699f639f882813b02ce65ee9e676fc7caa/pytest_mpl/plugin.py#L762-L763 https://github.com/matplotlib/pytest-mpl/blob/db0ea3699f639f882813b02ce65ee9e676fc7caa/pytest_mpl/plugin.py#L930-L931 See the [release notes](https://pluggy.readthedocs.io/en/stable/changelog.html#features) and [docs](https://pluggy.readthedocs.io/en/stable/index.html#wrappers).