In my opinion, nothing should pop up without explicit user action (keypress, mouse click). Every would-be pop-up should be pop-under, with some cue (visual or

In my opinion, nothing should pop up without explicit user action (keypress, mouse click). Every would-be pop-up should be pop-under, with some cue (visual or otherwise) to inform the user that something may deserve attention (e.g. flashing taskbar entry or tray icon). Note also that this is a general problem not restricted to Windows.