JEP 492 spec: https://cr.openjdk.org/~gbierman/jep492/jep492-20241101/specs/flexible-constructor-bodies-jls.html

Assertion:
If C occurs in a static context, then i has no immediately enclosing instance. Let S be the nearest static method declaration, static field declaration, or static initializer that encloses the declaration of C. If the nearest static method declaration, static field declaration, or static initializer that encloses the class instance creation expression is not S, then a compile-time error occurs.

Class Local1 in the code sample below is declared as part of the static field initializer (in a static context), and it's instantiated in a different static context.
The instance creation is supposed to fail in this case, but it succeeds.

class Test {
    static int field = switch (1) {
        case 1 -> {
            class Local1 {
                class Local2 {
                    public static void m() {
                        new Local1(); // does not fail
                    }
                }
            }
            yield 1;
        }
        default -> 2;
    };
}