Prior to JDK 26, the `javac` compiler did not apply a JLS mandated capture conversion when deciding if a method reference is compatible with a given function type. This could lead the `javac` compiler to accept code like the following:

```
    import java.util.function.Supplier;

    class Test {
        interface X<T> {
            X<T> self();
        }
        static X<?> makeX() {return null;}
        static <R> X<R> create(Supplier<? extends R> supplier) {return null;}
        static X<X<?>> methodRef() {
            return create(Test::makeX).self();
        }
    }
```

Starting from JDK 26, the `javac` compiler will apply the JLS mandated capture conversion when deciding if a method reference is compatible with a given function type. Code, like that in the sample above, will be rejected.