EnsuresNonNull failing on generic method parameters

Hello,

I have come across an issue while using @EnsuresNonNull on method parameters with certain generic types.

If I have the following method

public class CollectionContracts {

    @EnsuresNonNull("#1")
    public static <T extends Collection<E>, E> @NonNull T requireNotEmpty(T collection) {
        if(collection == null) {
            throw new IllegalArgumentException("Collection was null");
        }
        if(collection.isEmpty()) {
            throw new IllegalArgumentException("Collection was empty");
        }
        return collection;
    }
}

the compilation fails with the following error message:

[...]/CollectionContracts.java:4:59
java: [contracts.postcondition] postcondition of requireNotEmpty is not satisfied.
  found   : no information about collection
  required: collection is @NonNull

If I change the signature to

    @EnsuresNonNull("#1")
    public static <E> @NonNull Collection<E> requireNotEmpty(Collection<E> collection) {

everything work as I would expect.

I am using checker-framework version 3.42.0 with maven-compiler-plugin 3.12.1