diff --git a/.github/workflows/windows-ci.yml b/.github/workflows/windows-ci.yml
new file mode 100644
index 00000000..ca587d50
--- /dev/null
+++ b/.github/workflows/windows-ci.yml
@@ -0,0 +1,66 @@
+name: Windows CI
+
+# Builds the kernel and CADability.Forms and runs both test projects on Windows. There CADability.Tests
+# targets net8.0-windows and also runs the tests that need GDI+, WinForms or OpenGL (e.g. the
+# comparison of the GDI+ conversions in CADability.Forms with the kernel, and the rendering of
+# geometry compared against reference bitmaps), which the Linux CI compiles out (issue #412).
+
+on:
+  pull_request:
+  push:
+    branches:
+      - master
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+concurrency:
+  group: windows-ci-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  build-and-test:
+    runs-on: windows-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          # ACadSharp is built from source (external/ACadSharp submodule, which
+          # itself pulls in CSUtilities as a submodule)
+          submodules: recursive
+
+      - name: Setup .NET SDK
+        uses: actions/setup-dotnet@v4
+        with:
+          # ACadSharp's TargetFrameworks include net10.0, so restore needs the .NET 10 SDK.
+          # The test projects target net8.0 (net8.0-windows), so its runtimes are installed as well.
+          dotnet-version: |
+            8.0.x
+            10.0.x
+
+      - name: Build the kernel
+        run: dotnet build CADability/CADability.csproj -c Release
+
+      - name: Build CADability.Forms
+        run: dotnet build CADability.Forms/CADability.Forms.csproj -c Release
+
+      - name: Run CADability.Tests
+        run: >
+          dotnet test tests/CADability.Tests/CADability.Tests.csproj -c Release
+          --logger "trx;LogFileName=CADability.Tests.trx"
+          --results-directory TestResults
+
+      - name: Run CADability.ImportTests
+        if: success() || failure()
+        run: >
+          dotnet test tests/CADability.ImportTests/CADability.ImportTests.csproj -c Release
+          --logger "trx;LogFileName=CADability.ImportTests.trx"
+          --results-directory TestResults
+
+      - name: Upload test results
+        if: success() || failure()
+        uses: actions/upload-artifact@v4
+        with:
+          name: test-results-windows
+          path: TestResults/*.trx
diff --git a/tests/CADability.ImportTests/DxfDimensionTest.cs b/tests/CADability.ImportTests/DxfDimensionTest.cs
index 6cc380d3..32b4b706 100644
--- a/tests/CADability.ImportTests/DxfDimensionTest.cs
+++ b/tests/CADability.ImportTests/DxfDimensionTest.cs
@@ -776,6 +776,12 @@ public void export_dimension_round_trips_as_a_dxf_dimension()
         // Header, the red layer "Dimensions" and a dimension style "LOGICAL" with values that are
         // nothing like CADability's defaults, so a translation is visible in the assertions:
         // DIMSCALE 2, DIMASZ 1.5, DIMEXO 0.5, DIMEXE 1.25, DIMTXT 3.5, DIMDEC 3.
+        /// <summary>
+        /// The fixtures are verbatim strings, so they have the line endings of the checkout: CRLF on Windows with
+        /// text=auto. A test that edits a fixture with Replace("...\n...") normalizes it to LF first.
+        /// </summary>
+        private static string Lf(string fixture) => fixture.Replace("\r\n", "\n");
+
         private const string StyledPrologue = @"  0
 SECTION
   2
@@ -993,8 +999,8 @@ public void import_dxf_dimension_translates_the_dimension_style()
         [TestMethod]
         public void import_dxf_dimension_uses_the_standard_style_of_the_file()
         {
-            string standard = LinearDimension.Replace("  3\nLOGICAL\n", "");
-            Assert.AreNotEqual(LinearDimension, standard, "the style reference should be removed");
+            string standard = Lf(LinearDimension).Replace("  3\nLOGICAL\n", "");
+            Assert.AreNotEqual(Lf(LinearDimension), standard, "the style reference should be removed");
             Project project = ImportProjectAsDimensions(StyledPrologue + standard + Epilogue);
             Dimension dim = SingleDimensionObject(project.GetActiveModel());
 
@@ -1211,11 +1217,11 @@ public void import_dxf_degenerate_dimension_keeps_its_block()
         {
             // drop the rotated subclass to make it an aligned dimension, and put the second
             // measured point straight above the first, along the normal
-            string degenerate = LinearDimension
+            string degenerate = Lf(LinearDimension)
                 .Replace("100\nAcDbRotatedDimension\n 50\n0.0\n", "")
                 .Replace(" 14\n100.0", " 14\n0.0")
                 .Replace(" 34\n0.0", " 34\n100.0");
-            Assert.AreNotEqual(LinearDimension, degenerate, "the fixture should have been changed");
+            Assert.AreNotEqual(Lf(LinearDimension), degenerate, "the fixture should have been changed");
             Model model = ImportAsDimensions(StyledPrologue + degenerate + Epilogue);
 
             Assert.AreEqual(1, model.Count, "it must not get lost");
@@ -1230,9 +1236,9 @@ public void import_dxf_degenerate_dimension_keeps_its_block()
         [TestMethod]
         public void import_dxf_dimension_text_override_keeps_the_measurement()
         {
-            string withText = LinearDimension.Replace("100\nAcDbAlignedDimension",
+            string withText = Lf(LinearDimension).Replace("100\nAcDbAlignedDimension",
                 "  1\nca. <> mm\n100\nAcDbAlignedDimension");
-            Assert.AreNotEqual(LinearDimension, withText, "the text override should be inserted");
+            Assert.AreNotEqual(Lf(LinearDimension), withText, "the text override should be inserted");
             Dimension dim = SingleDimensionObject(ImportAsDimensions(StyledPrologue + withText + Epilogue));
 
             dim.GetBoundingCube();
@@ -1389,8 +1395,8 @@ public void import_dxf_arc_length_dimension_does_not_share_the_style_of_a_linear
         public void import_dxf_dimension_translates_the_angle_format()
         {
             // DIMAUNIT (group code 275) 1 is degrees, minutes and seconds
-            string prologue = StyledPrologue.Replace("271\n3\n", "271\n3\n275\n1\n");
-            Assert.AreNotEqual(StyledPrologue, prologue, "DIMAUNIT should be set");
+            string prologue = Lf(StyledPrologue).Replace("271\n3\n", "271\n3\n275\n1\n");
+            Assert.AreNotEqual(Lf(StyledPrologue), prologue, "DIMAUNIT should be set");
             Dimension dim = SingleDimensionObject(ImportAsDimensions(prologue + LinearDimension + Epilogue));
 
             Assert.AreEqual(DimensionStyle.EAngleText.DegreeMinuteSecond, dim.DimensionStyle.AngleText);
diff --git a/tests/CADability.Tests/RendererRecoveryTests.cs b/tests/CADability.Tests/RendererRecoveryTests.cs
index 78d85af4..4487e7e8 100644
--- a/tests/CADability.Tests/RendererRecoveryTests.cs
+++ b/tests/CADability.Tests/RendererRecoveryTests.cs
@@ -3,6 +3,8 @@
 using System.Runtime.InteropServices;
 using CADability.GeoObject;
 using CADability.Substitutes;
+// with UseWindowsForms (the Windows build of the tests), System.Windows.Forms has a PaintEventArgs as well
+using PaintEventArgs = CADability.Substitutes.PaintEventArgs;
 
 namespace CADability.Tests
 {