Update CHANGELOG.md

CHANGELOG.md

@@ -2,6 +2,12 @@
 
 * There currently is no completion support for package references in csproj files. ([#1156](https://github.com/OmniSharp/omnisharp-vscode/issues/1156))
   * As an alternative, consider installing the [MSBuild Project Tools](https://marketplace.visualstudio.com/items?itemName=tintoy.msbuild-project-tools) extension by @tintoy.
+  
+## 1.16.0 _(Not Yet Released)_
+
+#### Editor
+
+* Improved diagnostics by refreshing them when the active editor changes or the current window is focused. (PR: [#2317](https://github.com/OmniSharp/omnisharp-vscode/pull/2317)) _(Contributed by [@SirIntruder](https://github.com/SirIntruder))
 
 ## 1.15.2 (May 15, 1018)