Unreal Engine Issues

Nanite mesh is shown with player collision

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 ...

Compiling Blueprints breaks socketed attachments of actors attached to non-root components

When blueprints are compiled, instances of those blueprints have their attachments detached and then reattached. Reattachments always occur on the RootComponent regardless of which component they we ...

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 ...

K2Node_FunctionEntry: Focusing "Name" property in Details panel changes function name to display format

Users can enter blueprint function names without spaces, for example PascalCase (MyFunctionName) or snake_case (my_function_name). The "My Blueprint" tab functionality for naming functions allow all ...

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 ...

Specular/Anisotropy problems with Nanite Meshes

Specular highlights can disappear with clearcoat materials, when "Clear Coat Enable Second Normal" is enabled ("r.ClearCoatNormal"). ...

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 ...

Map actor reconstruction does not reattach external non-root components

For two map placed actors, if one actor B's non root component is attached to another actor A, the attachment is not retained when actor A reruns its construction script, such as when moving actor A ...

FScopedEditorWorld doesn't clean up old world when going out of scope

In a commandlet, when FScopedEditorWorld exits, it leaves references behind and prevents garbage collection of the PersistentLevel and non-spatial actors. This leads to an issue when a second FScop ...