Welcome the Jabberwock!
Neos 5.0 and Flow 6.0 with an updated Neos UI 5.0 , an all-new Redirect Handler 3.0, PSR-7 and way more.
Read the release blog post on neos.io as well as the upgrade instructions as usual. And be aware that this is a major release, it raises the minimum PHP version to 7.2 and contains breaking changes that most likely will need adjustments in your code, too…
Here is a list of links to the changes:
- Neos 5.0.0 Change Log
- Flow 6.0.0 Change Log
Enjoy the newest Neos and Flow versions 
Thanks to everyone who contributed code, documentation, translations, bug reports, pull requests, organizational skills, …