Alert flag when there are subjects at war

[annulen]

There is alert flag that player's country is at war (which is somewhat redundant because of war buttons at the bottom of the screen), however there is no such flag when player countries are at peace but one or more subjects are at war. It can happen with tributaries and colonial nations. While it's possible to add them into watch list and monitor their events, it's possible to miss it accidentally, or forget that long war is still ongoing.