Fix v5 changelog (#302)

CHANGELOG.md

@@ -5,6 +5,8 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/), and this project
 adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+
 ## [5.0.0] - 2024-02-22
 
 ### Changed
@@ -111,7 +113,8 @@ provided.
 
 ## [1.0.0] - 2016-05-09
 
-[unreleased]: https://github.com/tumblr/tumblr.js/compare/v4.0.1...HEAD
+[unreleased]: https://github.com/tumblr/tumblr.js/compare/v5.0.0...HEAD
+[5.0.0]: https://github.com/tumblr/tumblr.js/releases/tag/v5.0.0
 [4.0.1]: https://github.com/tumblr/tumblr.js/releases/tag/v4.0.1
 [4.0.0]: https://github.com/tumblr/tumblr.js/releases/tag/v4.0.0
 [3.0.0]: https://github.com/tumblr/tumblr.js/releases/tag/v3.0.0