diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5aa6b6535..ccc4c9010 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -23,6 +23,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ### Changed
 
+* `window.fdc3` is now an optional property and may or may not be defined. Applications should now use `getAgent()` as the recommended way of retrieving a reference to the FDC3 API. ([#1386](https://github.com/finos/FDC3/pull/1386))
 * `Listener.unsubscribe()` was made async (the return type was changed from `void` to `Promise<void>`) for consistency with the rest of the API. ([#1305](https://github.com/finos/FDC3/pull/1305))
 * Added reference materials and supported platforms information for FDC3 in .NET via the [finos/fdc3-dotnet](https://github.com/finos/fdc3-dotnet) project. ([#1108](https://github.com/finos/FDC3/pull/1108))
 * The supported platforms page in the FDC3 documentation was moved into the API section as the information it provides all relates to FDC3 Desktop Agent API implementations. ([#1108](https://github.com/finos/FDC3/pull/1108))