It would be good to be able to further edit a string chosen via the GetOptions dropdown. Right now they are locked to only the options available. One use case would be able to choose from a drop down at first from a list of options, and decide to generalize it by introducing a glob pattern matching.
Since you cannot mix and match chosen options with edited string, you must specify two UPROPERTIES instead.
UCLASS(ClassGroup = MyGame, meta = (BlueprintSpawnableComponent, PrioritizeCategories = "MyGame", AutoCollapseCategories = "MyGame|Internal"))
class AMyGameRoom : public AActor
{
GENERATED_BODY()
public:
UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "MyGame", meta = (GetOptions = "GetGroupNames"))
TArray<FString> ActiveGroups;
UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "MyGame", meta = (GetOptions = "GetGroupNames"))
TArray<FString> ActiveGroupPatterns;
...
}