A long read but worth it.
One of the first things you’ll learn when looking at ARIA is that supporting keyboard navigation is fundamental. And the first step to understanding keyboard navigation is to understand what focus is. And this is where I tripped, because nobody knew (in detail) which elements could receive focus and which could not.
Having had a bit of experience testing browser compatibility (“CSS3 Transitions: Thank God We Have A Specification!”), I decided I would spend some time investigating. An ebook covering my findings is in the works and will be ready to make you lose focus in early 2016. But more importantly, the JavaScript variant of that book is available today:ally.js is a JavaScript library to help modern web applications with accessibility concerns by making accessibility simpler.
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Source: Making Accessibility Simpler, With Ally.js – Smashing Magazine
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