Window Selection Problem

I have been facing this intermittently occurring problem that I have tried to explain in this video (1:15 min run time). This problem occurs sometimes and disappear after a while somehow on its own or closing few Edge sessions or if I restart my machine. UiExplorer on the overlay container gives:

<wnd app='microsoftedge.exe' cls='Windows.UI.Core.CoreWindow' idx='1' title='Microsoft Edge' />

Seems like Microsoft Edge container (hidden?) stays there sometimes. Please help me in understanding the root cause and a solution. Thank You.