After completing a Stunt mission, Slam overlay persists

Same here, I've had the same issue with the "target" staying after mission ends, even when on-board in some occasions. Also had the text "return to session marker" stuck in the same manner.
The missions Toadilus​ is talking about was also awful, with the distance not properly registering. I only got after repeatedly slamming myself in the exact same way and finally randomly getting it.