diff --git a/ThScoreFileConverter/ThScoreFileConverter.csproj b/ThScoreFileConverter/ThScoreFileConverter.csproj
index 8b3e98a1..c8e8dffb 100644
--- a/ThScoreFileConverter/ThScoreFileConverter.csproj
+++ b/ThScoreFileConverter/ThScoreFileConverter.csproj
@@ -64,7 +64,7 @@
     </PackageReference>
     <PackageReference Include="LivetCask.Behaviors" Version="4.0.2" />
     <PackageReference Include="Prism.Unity" Version="8.1.97" />
-    <PackageReference Include="ReactiveProperty.WPF" Version="9.3.1" />
+    <PackageReference Include="ReactiveProperty.WPF" Version="9.3.4" />
     <PackageReference Include="StyleCop.Analyzers.Unstable" Version="1.2.0.507">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>