ally/query/focusable does not find scrollable elements

[rodneyrehm]

Internet Explorer 10-11 consider any scrollable container and its scrollable body focusable - no other browser does this.

<div style="width: 100px; height: 50px;">
   <div style="width: 500px; height: 40px;">scrollable content</div>
</div>

[rodneyrehm]

Wrong!

• IE10-11 consider the scroll container and its children focusable.
• Firefox considers the scroll container keyboard focusable (tabbable), but will not focus the container upon click.

[rodneyrehm]

is/focusable will correctly identify the element as focusable, if that's the browser's native behavior. query/focusable in "quick" mode (default) will not find this element, "strict" mode will.