Unreal Engine Issues
Unreal Engine Issues
Updating project modules causes custom blueprints to lose reference to parent class
UE - Gameplay - Blueprint - Jul 7, 2016When changing the name of a module or creating a new module, updating the _API of a class to the new module will cause blueprints based on this class to lose reference ...
Illegal reference to private object when cooking a child level sequence with a time warp track
zComponent - Archive - Apr 28, 2025Slack: [Link Removed] Another Slack: [Link Removed] Cook error:UATHelper: Cooking (Windows): LogSavePackage: Warning: UATHelper: Cooking (Windows): Referencers of MovieSceneTimeWarpSection /Gam ...
Editor memory leak when Actor's string variable contains characters close to/exceeding a million bytes
Tools - Dec 19, 2018Editor memory leak occurs when Actor's String Variable contains Characters(Char) close to/exceeding a million bytes ...
Level Instance: failed check in duplication code when embedding
UE - Engine Scaling - Streaming - Level Instances - Aug 2, 2021Mentioned in this UDN is the possibility that duplication of some actor fails because their BP as been deleted. ...
The drawing order of widgets becomes wrong when GlobalInvalidation is enabled,
UE - AI Workflows - UI Systems - Slate - Nov 26, 2021When trying to create a widget with specific steps, the drawing order may not be correct. This is not reproduced when Global Invalidation is disabled, and the state can be restored. This issue is pr ...
Enhanced Input: use-after-free in EvaluateInputComponentDelegates when a delegate forces a synchronous mapping rebuild
UE - Gameplay - Input - Sep 21, 2026Context UEnhancedPlayerInput::EvaluateInputComponentDelegates iterates the delegates that triggered this tick. For each one it resolves the action's state via FindActionInstanceData(DelegateAction) ...
Using HISM with Density Scaling enabled throws an Ensure when Foliage Quality is lowered
UE - Rendering - Features - Apr 5, 2022Using HISM with Density Scaling enabled throws an Ensure when Foliage Quality is lowered. ...
Opening Editor preferences window while simulating and pressing Play/Stop causes memory leak
UE - Foundation - Core - EditorLoader - Feb 3, 2020An open but minimized Editor Preferences window causes a memory leak while simulating and repeatedly pressing Play/Stop. ...
NDisplay hangs and stops responding on cluster event send
UE - Virtual Production - nDisplay - Nov 12, 2019"The test event is set up using the default CE port, but every time an event is sent through the launcher the display receives the input and processes it, however the launcher will "hang" and stop ...
Sequencer based Camera Shake throws an assertion when spammed
zComponent - Archive - Apr 7, 2022Activating a Sequencer based Camera Shake repetitively results in an assertion being thrown. Assertion failed: DestAllocationIndex != SourceAllocationIndex [File:D:\build\++UE5\Sync\Engine\Source\R ...