Is this using Slate/UMG, and if so, how is your UQuestObjective::GetObjectiveName function bound to your UI? Slate also requires FText, so I’m guessing it’s being converted somehow?
I’d also be curious to know whether you still see this issue with 4.11 (if it’s possible for you to test). Prior to 4.11, it was possible for a shared pointer to leak its reference count object under a very specific set of circumstances, and FText could cause this leak if used in a certain way.