diff --git a/src/Components/WebAssembly/Server/src/ComponentsWebAssemblyApplicationBuilderExtensions.cs b/src/Components/WebAssembly/Server/src/ComponentsWebAssemblyApplicationBuilderExtensions.cs
index c7292d991b76..7e2e0c10481d 100644
--- a/src/Components/WebAssembly/Server/src/ComponentsWebAssemblyApplicationBuilderExtensions.cs
+++ b/src/Components/WebAssembly/Server/src/ComponentsWebAssemblyApplicationBuilderExtensions.cs
@@ -86,6 +86,7 @@ private static StaticFileOptions CreateStaticFilesOptions(IFileProvider webRootF
         options.FileProvider = webRootFileProvider;
         var contentTypeProvider = new FileExtensionContentTypeProvider();
         AddMapping(contentTypeProvider, ".dll", MediaTypeNames.Application.Octet);
+        AddMapping(contentTypeProvider, ".webcil", MediaTypeNames.Application.Octet);
         // We unconditionally map pdbs as there will be no pdbs in the output folder for
         // release builds unless BlazorEnableDebugging is explicitly set to true.
         AddMapping(contentTypeProvider, ".pdb", MediaTypeNames.Application.Octet);