Long regexp naming rule fails to replace with empty string

[jskov-jyskebank-dk]

    @ParameterizedTest
    @CsvSource({
        "JRAftalegrundlagBackendServiceInterfaceContractInterfaceAftalegrundlag20200301AftalegrundlagAftalegrundlag, Aftalegrundlag"
    })
    void regexpExpressionTests(String input, String expected) {
        Naming sut = makeSut("REGEXP/JRAftalegrundlagBackendServiceInterfaceContractInterfaceAftalegrundlag20200301Aftalegrundlag/_/;");
        assertThat(sut.convertTypeName(input))
            .isEqualTo(expected);
    }

The above does replace with _. But cannot replace with // (empty)

(Per)

[jskov-jyskebank-dk]

Not sure what this was about. The test works fine now. Also on 0.10.6?!