app/proguard-rules.pro

@@ -23,7 +23,9 @@
 }
 -if @kotlinx.serialization.Serializable class **
 -keepclassmembers class <1> {
-   static **$$serializerInstance;
+# Keep Kotlinx Serialization generated serializer instances
+-keepclassmembers class ** {
+    static ** \]serializerInstance;
    kotlinx.serialization.KSerializer serializer(...);
 }