There are some features of Java 11 that I am not addressing in the book. It is by decision. The book is to novice programmers who learn Java just now. The change how nested classes access control changed in Java 11 is a topic that a developer should understand only later and presenting it would only have confused the novice programmer. The same way there is no comparison to older versions. You learn the state of the art Java, why learn the older version. (Well, yes, for a short while you may work on a project at a company that uses an older version, but then you will just accommodate to that.)
Nevertheless, I reworked the code samples of the book from Java 9 to Java 10/11 so that I extensively use the predefined type 'var' in the code samples.
As for Java 10 features: these features are also Java 11 features, they were not deleted from the new version, were they?