diff --git a/.github/workflows/build_artifacts.yml b/.github/workflows/build_artifacts.yml
index 36ffa01414..7cdd62e2e2 100644
--- a/.github/workflows/build_artifacts.yml
+++ b/.github/workflows/build_artifacts.yml
@@ -34,6 +34,7 @@ jobs:
                   dotnet-version: |
                       6.x
                       8.x
+                      9.x
 
             - name: Restore dependencies
               run: dotnet restore ${{ env.solution }}
diff --git a/Directory.packages.props b/Directory.packages.props
index b58226de08..8fa27d2bfd 100644
--- a/Directory.packages.props
+++ b/Directory.packages.props
@@ -26,7 +26,7 @@
     <PackageVersion Include="System.Net.Http" Version="4.3.4" />
     <PackageVersion Include="System.Text.RegularExpressions" Version="4.3.1" />
     <PackageVersion Include="VirtualizingWrapPanel" Version="1.5.8" />
-    <PackageVersion Include="XAMLTest" Version="1.2.2" />
+    <PackageVersion Include="XAMLTest" Version="1.3.0-ci602" />
     <PackageVersion Include="xunit" Version="2.6.2" />
     <PackageVersion Include="xunit.runner.visualstudio" Version="2.5.4" />
     <PackageVersion Include="Xunit.StaFact" Version="1.1.11" />
diff --git a/global.json b/global.json
index c19a2e057c..ccbe73ca13 100644
--- a/global.json
+++ b/global.json
@@ -1,6 +1,6 @@
 {
   "sdk": {
-    "version": "8.0.100",
+    "version": "9.0.300",
     "rollForward": "latestMinor"
   }
 }
diff --git a/tests/MaterialDesignThemes.UITests/MaterialDesignThemes.UITests.csproj b/tests/MaterialDesignThemes.UITests/MaterialDesignThemes.UITests.csproj
index c75b048ec9..2612cc5af3 100644
--- a/tests/MaterialDesignThemes.UITests/MaterialDesignThemes.UITests.csproj
+++ b/tests/MaterialDesignThemes.UITests/MaterialDesignThemes.UITests.csproj
@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFramework>net8.0-windows</TargetFramework>
+    <TargetFramework>net9.0-windows</TargetFramework>
     <IsPackable>false</IsPackable>
     <SignAssembly>false</SignAssembly>
     <UseWPF>true</UseWPF>
diff --git a/tests/MaterialDesignThemes.UITests/WPF/UpDownControls/DecimalUpDownTests.cs b/tests/MaterialDesignThemes.UITests/WPF/UpDownControls/DecimalUpDownTests.cs
index c65ff7fb8f..6cced0c83e 100644
--- a/tests/MaterialDesignThemes.UITests/WPF/UpDownControls/DecimalUpDownTests.cs
+++ b/tests/MaterialDesignThemes.UITests/WPF/UpDownControls/DecimalUpDownTests.cs
@@ -1,17 +1,26 @@
-using System.ComponentModel;
+using System.ComponentModel;
+using System.Globalization;
+using System.Threading;
 
 namespace MaterialDesignThemes.UITests.WPF.UpDownControls;
 
 public class DecimalUpDownTests(ITestOutputHelper output) : TestBase(output)
 {
-    [Fact]
-    public async Task NumericButtons_IncreaseAndDecreaseValue()
+    [Theory]
+    [InlineData("en-US")]
+    [InlineData("da-DK")]
+    [InlineData("fa-IR")]
+    [InlineData("ja-JP")]
+    [InlineData("zh-CN")]
+    public async Task NumericButtons_IncreaseAndDecreaseValue(string culture)
     {
         await using var recorder = new TestRecorder(App);
 
         var numericUpDown = await LoadXaml<DecimalUpDown>("""
-        <materialDesign:DecimalUpDown Value="1" />
+        <materialDesign:DecimalUpDown Value="1" ValueStep="0.1" />
         """);
+        await App.RemoteExecute<string>(SetCulture, [culture]);
+
         var plusButton = await numericUpDown.GetElement<RepeatButton>("PART_IncreaseButton");
         var minusButton = await numericUpDown.GetElement<RepeatButton>("PART_DecreaseButton");
         var textBox = await numericUpDown.GetElement<TextBox>("PART_TextBox");
@@ -22,8 +31,8 @@ public async Task NumericButtons_IncreaseAndDecreaseValue()
         await plusButton.LeftClick();
         await Wait.For(async () =>
         {
-            Assert.Equal("2", await textBox.GetText());
-            Assert.Equal(2, await numericUpDown.GetValue());
+            Assert.Equal(Convert.ToString(1.1, CultureInfo.GetCultureInfo(culture)), await textBox.GetText());
+            Assert.Equal((decimal)1.1, await numericUpDown.GetValue());
         });
 
         await minusButton.LeftClick();
@@ -34,6 +43,11 @@ await Wait.For(async () =>
         });
 
         recorder.Success();
+
+        static void SetCulture(Application _, string culture)
+        {
+            Thread.CurrentThread.CurrentCulture = CultureInfo.GetCultureInfo(culture);
+        }
     }
 
     [Fact]