Based on https://github.com/zendframework/zend-servicemanager/releases/tag/release-2.3.9 (commit 50968287d897101bdf03e47c6f35041f12aefb9c in this repo)

- [zendframework/zend-servicemanager#7506](https://github.com/zendframework/zf2/pull/7506) resolves issues when UTF-8 values are used in Mail headers, particularly addresses.
- [zendframework/zend-servicemanager#7507](https://github.com/zendframework/zf2/pull/7507) ensures that array values can be used with cookies.
- [zendframework/zend-servicemanager#7514](https://github.com/zendframework/zf2/pull/7514) ensures that multipart MIME messages can be added to `Laminas\Mail\Message` instances in such a way that they do not conflict with ZF2015-04.