In most desktop environments, the Tab key is a secret weapon in navigation—one tool that many users are accustomed to. Likewise, we can utilize the Tab key in HTML5 applications using the
tabindex property. This tells the browser the order in which to focus elements, each time the key is pressed.
Unfortunately, this isn't as straightforward as it looks with accordion widgets. We can't specify a
tabindex value in each section header and expect the Tab key events to work as expected. Instead, the default widget implementation provides a different kind of key navigation—the up and down arrow keys. Ideally, it would be useful to give users the ability to navigate through the accordion sections using the Tab key ...