diff --git a/src/Uno.UI/UI/ColorHelper.cs b/src/Uno.UI/UI/ColorHelper.cs
index 4df6787fb020..aa80035a01d5 100644
--- a/src/Uno.UI/UI/ColorHelper.cs
+++ b/src/Uno.UI/UI/ColorHelper.cs
@@ -1,9 +1,11 @@
-using System;
+// On the UWP branch, only include this file in Uno.UWP (as public Window.whatever). On the WinUI branch, include it in both Uno.UWP (internal as Windows.whatever) and Uno.UI (public as Microsoft.whatever)
+#if HAS_UNO_WINUI || !IS_UNO_UI_PROJECT
+using System;
 using System.ComponentModel;
 using Uno.Extensions;
 using WindowsColor = Windows/*Intentional space for WinUI upgrade tool*/.UI.Color;
 
-#if HAS_UNO_WINUI && IS_UNO_UI_PROJECT
+#if IS_UNO_UI_PROJECT
 namespace Microsoft.UI.Text;
 #else
 namespace Windows.UI.Text;
@@ -357,7 +359,7 @@ public static WindowsColor FromArgb(byte a, byte r, byte g, byte b)
 	];
 	#endregion
 
-	private unsafe static uint GetColorNameResourceId(WindowsColor color)
+	private static uint GetColorNameResourceId(WindowsColor color)
 	{
 		var hsl = color.ToHsl();
 		double h = hsl.H * 255.0;
@@ -428,3 +430,4 @@ private unsafe static uint GetColorNameResourceId(WindowsColor color)
 		}
 	}
 }
+#endif
diff --git a/src/Uno.UI/UI/Colors.cs b/src/Uno.UI/UI/Colors.cs
index 963bb0d574c5..438266dca91c 100644
--- a/src/Uno.UI/UI/Colors.cs
+++ b/src/Uno.UI/UI/Colors.cs
@@ -1,10 +1,12 @@
-using System;
+// On the UWP branch, only include this file in Uno.UWP (as public Window.whatever). On the WinUI branch, include it in both Uno.UWP (internal as Windows.whatever) and Uno.UI (public as Microsoft.whatever)
+#if HAS_UNO_WINUI || !IS_UNO_UI_PROJECT
+using System;
 using System.Collections.Generic;
 using System.Text;
 
 using Color = global::Windows/*Intentional space for WinUI upgrade tool*/.UI.Color;
 
-#if HAS_UNO_WINUI && IS_UNO_UI_PROJECT
+#if IS_UNO_UI_PROJECT
 namespace Microsoft.UI
 #else
 namespace Windows.UI
@@ -564,3 +566,4 @@ private static byte ToByte(char c)
 		public static Color YellowGreen => _yellowGreen ??= FromInteger(unchecked((int)0xFF9ACD32));
 	}
 }
+#endif
diff --git a/src/Uno.UI/UI/Text/FontWeights.cs b/src/Uno.UI/UI/Text/FontWeights.cs
index 473186f8cfd7..e0ad16cd18fb 100644
--- a/src/Uno.UI/UI/Text/FontWeights.cs
+++ b/src/Uno.UI/UI/Text/FontWeights.cs
@@ -1,8 +1,10 @@
-using System;
+// On the UWP branch, only include this file in Uno.UWP (as public Window.whatever). On the WinUI branch, include it in both Uno.UWP (internal as Windows.whatever) and Uno.UI (public as Microsoft.whatever)
+#if HAS_UNO_WINUI || !IS_UNO_UI_PROJECT
+using System;
 using System.Collections.Generic;
 using System.Text;
 
-#if HAS_UNO_WINUI && IS_UNO_UI_PROJECT
+#if IS_UNO_UI_PROJECT
 using Windows.UI.Text;
 namespace Microsoft.UI.Text
 #else
@@ -47,3 +49,4 @@ partial class FontWeights
 		public static FontWeight UltraBlack => _extraBlack ??= new FontWeight(950);
 	}
 }
+#endif