Unreal Engine Issues

Montage Editor calls NotifyEnds of AnimNotifyState even when paused

In the Animation Montage Editor, NotifyEnd is unexpectedly called when a time marker is in the middle of an AnimNotifyState and the animation preview gets paused. Because the Animation Montage Edito ...

Non-existing config file loading could cause memory leak

The cause of this problem is the Engine has code paths which register a new allocated object to Map without deleting the previous object. In the repro project, whenever hitting Space Bar, the level ...

Mass Agent Component implementation triggers Aggressive Default Reference Replacement ensure

Workaround: Construct the DefaultSubobject with ... = CreateDefaultSubobject<UMassAgentComponent>(TEXT("MASS"), true); The issue appears to be that the DefaultSubobject holds a pointer to the CDO ...

In-editor hitch when deleting one actor in a world with many loaded actors

When editing a level with many actors (1000+), deleting an actor results in a noticeable hitch: the editor becomes unresponsive for seconds. This hitch becomes longer the more actors are loaded and ...

Chaos Vehicle does not make them CCD

AWheeledVehiclePawn class tries to use CCD in the constructor, but Mesh->BodyInstance.bUseCCD = true this code does not work to activate CCD because Physics Assets could not be available at this ...

Pre-UE5 serialized FVariant FVector data corruption when deserialized in UE5

FVariant is a struct that implements a union of data types, including FVector. When assigning an FVariant an FVector value in engine versions UE 4.27 or earlier, the FVariant will deserialize incorr ...

Reset Instance Changes to Blueprint Defaults does not reregister components

For map placed blueprint actors with components with property modifications, when triggering Reset Instance Changes to Blueprint Default from the actor instance's Details panel, any components with ...

"StaticFindFirstObject: Ambiguous object name" on delegates with timelines in packed level actors

"Build All Levels" does not re-AddNavigationSystemToWorld

The Build All Levels editor action cleans up the world's NavDataSet (UNavigationSystemV1::NavDataSet) as pre-rebuild world cleanup by calling: SetNavigationSystem(nullptr); inside UWorld::Cleanu ...

PDI-DrawPoint - Zoomfactor being calculated incorrectly

A licensee has reported that the ZoomFactor variable inside of the DrawPoint function is being calculated incorrectly. It currently is calculated using the lesser of the projection matrix's horizont ...