Thanks for posting this! (I’m the book’s author.)<p>– The whole book is free to read online.<p>– This chapter gives an overview of what’s new in each ECMAScript version: <a href="https://exploringjs.com/js/book/ch_new-javascript-features.html#ch_new-javascript-features" rel="nofollow">https://exploringjs.com/js/book/ch_new-javascript-features.h...</a>