1 files changed, 1 insertions, 1 deletions

diff --git a/src/wixext/ComPlusExtensionFactory.cs b/src/wixext/ComPlusExtensionFactory.cs
index d9405867..76b51bff 100644
--- a/src/wixext/ComPlusExtensionFactory.cs
+++ b/src/wixext/ComPlusExtensionFactory.cs
@@ -8,7 +8,7 @@ namespace WixToolset.ComPlus
 
     public class ComPlusExtensionFactory : BaseExtensionFactory
     {
-        protected override IEnumerable<Type> ExtensionTypes => new[]
+        protected override IReadOnlyCollection<Type> ExtensionTypes => new[]
         {
             typeof(ComPlusCompiler),
             typeof(ComPlusExtensionData),