Fixes PrintPreviewControl displays a black preview page after assigning an empty PrintDocument

src/System.Windows.Forms/System/Windows/Forms/Printing/PrintPreviewControl.cs

@@ -690,7 +690,11 @@ private void DrawPages(Graphics g, Rectangle rect, PreviewPageInfo[] pages, Brus
             {
                 Rectangle box = pageRenderArea[i];
                 g.DrawRectangle(Pens.Black, box);
-                using (var brush = ForeColor.GetCachedSolidBrushScope())
+
+                // Default page fill is white (paper); an explicitly set ForeColor is still honored,
+                // as it always has been.
+                Color pageColor = _isForeColorSet ? ForeColor : Color.White;
+                using (var brush = pageColor.GetCachedSolidBrushScope())
                 {
                     g.FillRectangle(brush, box);
                 }

src/test/unit/System.Windows.Forms/System/Windows/Forms/Printing/PrintPreviewControlTests.cs

@@ -4,6 +4,7 @@
 #nullable disable
 
 using System.Drawing;
+using System.Drawing.Printing;
 
 namespace System.Windows.Forms.Tests;
 
@@ -68,6 +69,57 @@ public void PrintPreviewControl_ForeColorReset_ShouldSerializeReturnsFalse()
         Assert.Equal(SystemColors.ControlText.ToArgb(), control.ForeColor.ToArgb());
     }
 
+    [WinFormsFact]
+    public void PrintPreviewControl_PageWithNoImage_DefaultForeColor_RendersWhite()
+    {
+        // Regression test for #14838: a page with no drawable content (e.g. from an empty
+        // PrintDocument), with ForeColor left at its default, must render as white paper,
+        // not as a solid black rectangle.
+        using PrintPreviewControl control = new()
+        {
+            Size = new Size(200, 200)
+        };
+
+        control.CreateControl();
+
+        PreviewPageInfo[] pageInfo = [new(image: null, physicalSize: new Size(850, 1100))];
+        control.TestAccessor.Dynamic._pageInfo = pageInfo;
+
+        using Bitmap bitmap = new(control.Width, control.Height);
+        control.DrawToBitmap(bitmap, new Rectangle(Point.Empty, control.Size));
+
+        // The single page fills nearly the whole control, so the center pixel lands well
+        // inside the page interior, away from its 1px black border.
+        Color centerPixel = bitmap.GetPixel(bitmap.Width / 2, bitmap.Height / 2);
+
+        Assert.Equal(Color.White.ToArgb(), centerPixel.ToArgb());
+    }
+
+    [WinFormsFact]
+    public void PrintPreviewControl_PageWithNoImage_ExplicitForeColor_RendersForeColor()
+    {
+        // ForeColor has driven the page background fill since the original .NET Framework port;
+        // an explicitly set value must still be honored (see PR #14857 discussion), not overridden
+        // by the white default that only applies when ForeColor was never set.
+        using PrintPreviewControl control = new()
+        {
+            ForeColor = Color.Red,
+            Size = new Size(200, 200)
+        };
+
+        control.CreateControl();
+
+        PreviewPageInfo[] pageInfo = [new(image: null, physicalSize: new Size(850, 1100))];
+        control.TestAccessor.Dynamic._pageInfo = pageInfo;
+
+        using Bitmap bitmap = new(control.Width, control.Height);
+        control.DrawToBitmap(bitmap, new Rectangle(Point.Empty, control.Size));
+
+        Color centerPixel = bitmap.GetPixel(bitmap.Width / 2, bitmap.Height / 2);
+
+        Assert.Equal(Color.Red.ToArgb(), centerPixel.ToArgb());
+    }
+
     [Fact]
     public void ShowPrintPreviewControlHighContrast_BackColorIsCorrect()
     {