diff --git a/core/reflection.jvm/reflection.pro b/core/reflection.jvm/reflection.pro
index d2c319add8b..25caf9604bb 100644
--- a/core/reflection.jvm/reflection.pro
+++ b/core/reflection.jvm/reflection.pro
@@ -31,3 +31,7 @@
     public boolean containsKey(java.lang.Object);
     public kotlin.reflect.jvm.internal.pcollections.HashPMap minus(java.lang.Object);
 }
+
+# This is needed because otherwise ProGuard strips generic signature of this class (even though we pass `-keepattributes Signature` above)
+# See KT-23962 and https://sourceforge.net/p/proguard/bugs/482/
+-keep class kotlin.reflect.jvm.internal.impl.protobuf.GeneratedMessageLite$ExtendableMessageOrBuilder