diff --git a/src/modules/previewpane/UnitTests-GcodeThumbnailProvider/UnitTests-GcodeThumbnailProvider.csproj b/src/modules/previewpane/UnitTests-GcodeThumbnailProvider/UnitTests-GcodeThumbnailProvider.csproj
index bb94790a39..10aa82a5c0 100644
--- a/src/modules/previewpane/UnitTests-GcodeThumbnailProvider/UnitTests-GcodeThumbnailProvider.csproj
+++ b/src/modules/previewpane/UnitTests-GcodeThumbnailProvider/UnitTests-GcodeThumbnailProvider.csproj
@@ -24,7 +24,6 @@
   </ItemGroup>
 
   <ItemGroup>
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     <PackageReference Include="Moq" Version="4.16.1" />
     <PackageReference Include="MSTest.TestAdapter" Version="2.2.3" />
     <PackageReference Include="MSTest.TestFramework" Version="2.2.3" />
diff --git a/src/modules/previewpane/UnitTests-PdfThumbnailProvider/UnitTests-PdfThumbnailProvider.csproj b/src/modules/previewpane/UnitTests-PdfThumbnailProvider/UnitTests-PdfThumbnailProvider.csproj
index 7326db5573..3499eded00 100644
--- a/src/modules/previewpane/UnitTests-PdfThumbnailProvider/UnitTests-PdfThumbnailProvider.csproj
+++ b/src/modules/previewpane/UnitTests-PdfThumbnailProvider/UnitTests-PdfThumbnailProvider.csproj
@@ -24,7 +24,6 @@
   </ItemGroup>
 
   <ItemGroup>
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     <PackageReference Include="Moq" Version="4.16.1" />
     <PackageReference Include="MSTest.TestAdapter" Version="2.2.3" />
     <PackageReference Include="MSTest.TestFramework" Version="2.2.3" />
diff --git a/src/modules/previewpane/UnitTests-StlThumbnailProvider/UnitTests-StlThumbnailProvider.csproj b/src/modules/previewpane/UnitTests-StlThumbnailProvider/UnitTests-StlThumbnailProvider.csproj
index b1e43cf3f6..3028a57272 100644
--- a/src/modules/previewpane/UnitTests-StlThumbnailProvider/UnitTests-StlThumbnailProvider.csproj
+++ b/src/modules/previewpane/UnitTests-StlThumbnailProvider/UnitTests-StlThumbnailProvider.csproj
@@ -24,7 +24,6 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="Castle.Core" Version="4.4.1" />
     <PackageReference Include="Moq" Version="4.16.1" />
     <PackageReference Include="MSTest.TestAdapter" Version="2.2.3" />
     <PackageReference Include="MSTest.TestFramework" Version="2.2.3" />
diff --git a/src/modules/previewpane/UnitTests-SvgThumbnailProvider/UnitTests-SvgThumbnailProvider.csproj b/src/modules/previewpane/UnitTests-SvgThumbnailProvider/UnitTests-SvgThumbnailProvider.csproj
index 4f4b89ac0e..0f9fa187a4 100644
--- a/src/modules/previewpane/UnitTests-SvgThumbnailProvider/UnitTests-SvgThumbnailProvider.csproj
+++ b/src/modules/previewpane/UnitTests-SvgThumbnailProvider/UnitTests-SvgThumbnailProvider.csproj
@@ -20,7 +20,6 @@
   <Import Project="..\..\..\Version.props" />
 
   <ItemGroup>
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     <PackageReference Include="Moq" Version="4.16.1" />
     <PackageReference Include="MSTest.TestAdapter" Version="2.2.3" />
     <PackageReference Include="MSTest.TestFramework" Version="2.2.3" />