diff --git a/eng/Version.Details.xml b/eng/Version.Details.xml
index 3cb157d95c..14235dfa78 100644
--- a/eng/Version.Details.xml
+++ b/eng/Version.Details.xml
@@ -17,13 +17,13 @@
       <Uri>https://dev.azure.com/devdiv/DevDiv/_git/vs-code-coverage</Uri>
       <Sha>10709af4e2abc77a137e8027c8724ec78ffa442c</Sha>
     </Dependency>
-    <Dependency Name="MSTest" Version="4.5.0-preview.26459.10">
+    <Dependency Name="MSTest" Version="4.5.0-preview.26459.12">
       <Uri>https://github.com/microsoft/testfx</Uri>
-      <Sha>aec661618252e3430496387a9dd29825f6b0e35b</Sha>
+      <Sha>0989da8c698e9a960088b698d668e54413e2199a</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.Testing.Platform" Version="2.5.0-preview.26459.10">
+    <Dependency Name="Microsoft.Testing.Platform" Version="2.5.0-preview.26459.12">
       <Uri>https://github.com/microsoft/testfx</Uri>
-      <Sha>aec661618252e3430496387a9dd29825f6b0e35b</Sha>
+      <Sha>0989da8c698e9a960088b698d668e54413e2199a</Sha>
     </Dependency>
   </ToolsetDependencies>
 </Dependencies>
diff --git a/eng/Versions.props b/eng/Versions.props
index c92f9778e2..5200ddb30a 100644
--- a/eng/Versions.props
+++ b/eng/Versions.props
@@ -10,7 +10,7 @@
     <MicrosoftDotNetBuildTasksTemplatingPackageVersion>11.0.0-beta.26459.9</MicrosoftDotNetBuildTasksTemplatingPackageVersion>
     <MicrosoftTestingExtensionsCodeCoverageVersion>18.12.0-preview.26459.2</MicrosoftTestingExtensionsCodeCoverageVersion>
     <!-- empty line to avoid merge conflicts for darc PRs to update CC and MSTest+MTP -->
-    <MSTestVersion>4.5.0-preview.26459.10</MSTestVersion>
-    <MicrosoftTestingPlatformVersion>2.5.0-preview.26459.10</MicrosoftTestingPlatformVersion>
+    <MSTestVersion>4.5.0-preview.26459.12</MSTestVersion>
+    <MicrosoftTestingPlatformVersion>2.5.0-preview.26459.12</MicrosoftTestingPlatformVersion>
   </PropertyGroup>
 </Project>
diff --git a/test/.editorconfig b/test/.editorconfig
index cf74f1f347..85d1d6ad7b 100644
--- a/test/.editorconfig
+++ b/test/.editorconfig
@@ -34,6 +34,7 @@ dotnet_diagnostic.CA2201.severity = none            # CA2201: Do not raise reser
 dotnet_diagnostic.CA3075.severity = none            # CA3075: Insecure DTD processing in XML
 
 dotnet_diagnostic.IDE0060.severity = none           # IDE0060: Remove unused parameter
+dotnet_diagnostic.IDE0300.severity = suggestion     # IDE0300: Simplify collection initialization
 
 dotnet_diagnostic.MSTEST0001.severity = warning     # MSTEST0001: Explicitly enable or disable tests parallelization
 dotnet_diagnostic.MSTEST0016.severity = warning     # MSTEST0016: Test class should have test method