diff --git a/internal/impl/message_reflect.go b/internal/impl/message_reflect.go
index cff9067..f5f7f2b 100644
--- a/internal/impl/message_reflect.go
+++ b/internal/impl/message_reflect.go
@@ -330,7 +330,7 @@
 
 	if fd.IsExtension() {
 		if fd.ContainingMessage().FullName() != mi.Desc.FullName() {
-			// TODO(blocks): Should this be exact containing message descriptor match?
+			// TODO: Should this be exact containing message descriptor match?
 			panic("mismatching containing message")
 		}
 		if !mi.Desc.ExtensionRanges().Has(fd.Number()) {