Hi
I am trying to make the session as stateful. Unfortunately, in restoring I get a serialization error on the GridDragSource Vaadin class.
org.apache.coyote.http11.Http11Processor.service Error processing request
java.lang.ClassCastException: cannot assign instance of java.lang.invoke.SerializedLambda to field com.vaadin.ui.components.grid.Gri
dDragSource.dragDataGenerator of type com.vaadin.data.provider.DataGenerator in instance of com.vaadin.ui.components.grid.GridDragSource
at java.io.ObjectStreamClass$FieldReflector.setObjFieldValues(ObjectStreamClass.java:2133)
at java.io.ObjectStreamClass.setObjFieldValues(ObjectStreamClass.java:1305)
at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:2251)
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