I have noticed that Quick Documentation is not locating referenced documentation in links and displays instead "The page cannot be displayed" HTTP 401? error.
Additionally, if you click elsewhere on the page the Quick Documentation does not automatically close and if you leave it up and Ctrl-Q the previous documention and the current will both be open.
See screenshot. Here I Ctrl-Q for SetStyle, then Ctrl-Q for ControlStyles (I did not click the link!) finally, I Ctrl-Q for PaintEventArgs then clicked the link for Paint.
I have found that by clicking off the popup window and pressing 'Esc' the popups close one at a time in Z-order.
Attachment not added (general error): "QuckDocError.png"