[enhancement] Show Confirmation Window on the same Monitor

[masgo]

I am using KeeAgent together with Putty/Kitty in Windows with multiple monitors connected. Often, my putty window is on a secondary monitor. I have selected "Always require user confirmation...". The pop-up appears always on the main monitor. This is a problem, because sometimes it appears unexcpected (e.g. sudo timed out and auth is needed again), then it might happen, that I unintentionally press enter, which equals to "no".

It would be nice if it would appear in front of the requesting window. Or, as an alternative, on the same screen as the window which currently has the focus.

#231 seems slightly related.