diff --git a/release-notes.md b/release-notes.md
index 425b154360c55d19be7b12c2ca30b876758a2a23..13cfabac59210b8411426e431939a01c1ea02060 100644
--- a/release-notes.md
+++ b/release-notes.md
@@ -32,6 +32,7 @@ This release covers three important milestones: F# 5, Visual Studio 16.8, and .N
 
 ### FSharp Core 5.0.0
 
+* [Performance improvement](https://github.com/dotnet/fsharp/pull/10188) to core collections Set and Map by [Victor Baybekov](https://github.com/buybackoff) 
 * Consistent behavior for empty/non-existent slices for lists, strings, arrays, 2D arrays, 3D arrays, and 4D arrays
 * Support for fixed-index slices in 3D and 4D arrays
 * Support for negative indexes (in preview)