Enemy Troops don't Despawn

[Deantwo]

(This issue happened in an old-style city, but it is still an issue for new-style.)

Spacecraft berthed troops that are on the surface of a world are supposed to despawn when the spacecraft leaves the solar system.
This does not seem to be the case.

It is almost impossible to locate enemy troops or avatars on your world.
Ceruleas captured my capital city, yet again, and left some troops around on the military flags. A couple troops were also hiding some random place in a forest. But there are still enemy units on my world somewhere.

I would love it if police stations or maybe some military building would highlight locations of enemy units. This could be as simple as showing them on the world map, or have police helicopters circling over their heads with a spotlight pointed at them.
The highlighting could be delayed by 13 minutes or something, so an attacker can outrun it and try to keep ahead of defenders.

On the topic of defense, maybe a world with an active military base could spawn encounters for enemy units. Small squads of soldiers taken from the military base's barracks.
Related: (Idea thread) Empire Defense Fleet and Encounters

[Deantwo]

My capital city Rævehjerte is right now reporting the presents of an enemy Weltreich troop, but I have not been able to find one anywhere. And before that I was still unable to build a base because seemingly is an enemy Weltreich unit somewhere else on the world, Tail V.

EDIT: Found the enemy troop hiding in my carpenter, I shot him and my world in no longer under attack. Only took me ~4 days to find the troop...