diff --git a/changelog/upgrade-notes.md b/changelog/upgrade-notes.md
index 5836bae2e0..f9db712bfe 100644
--- a/changelog/upgrade-notes.md
+++ b/changelog/upgrade-notes.md
@@ -4,7 +4,7 @@
 
 #### Units of the `hitTolerance` option fixed
 
-Previously, the `hitTolerance` option of the map's `getFeaturesAtPixel()`, `forEachFeatureAtPixel()` and `hasFeatureAtPixel()` methods behaved differntly depending on the `devicePixelRatio` (or the `pixelRatio` of the map). Now this is fixed, the `hitTolerance`'s units are css pixels.
+Previously, the `hitTolerance` option of the map's `getFeaturesAtPixel()`, `forEachFeatureAtPixel()` and `hasFeatureAtPixel()` methods behaved differntly depending on the `devicePixelRatio` (or the `pixelRatio` of the map), because the original value was internally multiplied by the device pixel ratio twice instead of just once. Now this is fixed. **Note**: The `hitTolerance`'s units are css pixels. The documentation was updated to reflect this.
 
 If your application adjusts for that with code like
 ```js