Chrome Version: 66.0.3359.181 
Windows 10

Calling IAccessible2::get_Focus() doesn't take into account which tab or control has the focus in Chrome. It does work within the scope of a page, but not globally.

If the windows input focus is on the URL entry box, calling get_Focus() on the IAccessible for a web page root object will return the web page object. It should return VT_EMPTY indicating the page does not have the focus. Vice versa, when the page does have the focus and you query a different page or the URL bar, they also return a valid focus.

There should only be one focus object in Chrome, which is what get_Focus() should return regardless of which IAccessible object it is called on.

This bug causes a problem if a screen reader is launched after chrome has already started. The screen reader cannot determine where the keyboard focus is in Chrome so doesn't read the correct item. Once the focus has moved and focus events are fired, the screen reader can track the focus.