[SIL.WIndows.Forms] In CustomDropDown, fixed timer check (#1433)

Author: imnasnainaec

CHANGELOG.md

@@ -16,6 +16,10 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## [Unreleased]
 
+### Fixed
+
+- [SIL.Windows.Forms] In `CustomDropDown.OnOpening`, fixed check that triggers timer to stop.
+
 ## [16.0.0] - 2025-05-20
 
 ### Added

SIL.Windows.Forms/Widgets/CustomDropDown.cs

@@ -184,8 +184,11 @@ protected override void OnOpening(System.ComponentModel.CancelEventArgs e)
 			timer.Tick += delegate
 			{
 				Opacity += 0.1;
-				if (Opacity == 1f)
+				if (Opacity > .99)
+				{
+					Opacity = 1f;
 					timer.Stop();
+				}
 			};
 
 			timer.Start();