What does the green outline of the “preferred position” markers mean?

Question

Trying to decide which hero to put in which spot, I noticed that some heroes have a green outline around several of the "preferred position" markers.

What does that green outline mean? Does it have something to do with ranged attacks?

The picture is from the status screen of an Arbalest.

Answer 1

The green circles show which party members the character can target with their support skills.

In this case, they show that Battlefield Bandage can only hit the front three party members, allowing you to plan your positions accordingly.