Might as well put these reproduction steps here since it hasn't been mentioned yet.
(Disclaimer: this is second-hand information as I have not experienced the bug myself, so I don't know how accurate this is. Also not sure if this is related to the bug in the OP or if it's a different bug).
1. Load into a map while you're already in a party, the other person(s) in the party should also be in the same map as you and be near you(?), i.e. within range of your ground-targeted skills. Also make sure you don't have anything targeted.
2. Leave the party.
3. Create a squad.
4. Try to use a ground-targeted skill.
5. Notice ground target skills are locked to your feet.
Issue goes away when leaving/rejoining the map by any means OR by leaving the squad and rejoining a party.