Ask HN: How do I learn JavaScript?

I feel like I would like to learn modern JavaScript (as supported by the most recent version of V8) from the very basic to the perfect and complete level (which makes the whole point of the question, ways to mediocre proficiency are countless and obvious). I believe this is possible (and maybe not even hard) as I only mean the language itself - no browser APIs, no frameworks/libraries/tooling, no patterns and practices beyond those necessary to understand the features and the quirks of the language itself, what they can be used for and how to deal with them correctly. Where do I go and how hard is this actually going to be?