Javadoc produces wrong Java API links

gradle-5.0 (update to 5.1 is just running)
plugin java-library
task javadoc

javadoc {
options {
addBooleanOption(‘html5’, true)
setMemberLevel(JavadocMemberLevel.PUBLIC)
links(‘https://docs.oracle.com/en/java/javase/11/docs/api/’)
}
}

This task produces the correct HTML. Most is ok. All internal links are correct. BUT: All links to Java are wrong. Example for List<>:

should: https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/List.html
is: https://docs.oracle.com/en/java/javase/11/docs/api/java/util/List.html

In the URL, the module name is missing, as has been correct with Java 8.

How can i get this right?

TIA
QNo