wrongs visibility state when window loses focus

[nivcaner]

If I switch to another window, I still get Visibility.state() == visible.
This works fine if I switch to another tab.

Only problem is when switching window

[ai]

It is part of current Page Visibility realization in browsers, because you can view other unfocuced window if windows are not at full screen.

[mastef]

but does this actually mean that the tab in the unfocused window is visible?