diff --git a/CHANGELOG.md b/CHANGELOG.md
index 20d1c9bf5..a7c9269ad 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 ### Fixed
 - Mastodon API: Inability to get some local users by nickname in `/api/v1/accounts/:id_or_nickname`
 - Mastodon API: Blocks are now treated consistently between the Streaming API and the Timeline APIs
+- ActivityPub: Correct addressing of Undo.
 
 ## [1.0.90] - 2019-09-30
 ### Security