Unreal Engine Issues
Unreal Engine Issues
Renaming a BP interface function/event breaks all existing uses of that function/event
UE - Gameplay - May 24, 2018If you rename a blueprint interface function or event that is used somewhere in a blueprint, it will break the usage of that function/event. If it was a function, it will actually delete all the BP ...
Sequencer does not save asset variables in event struct
UE - Anim - Sequencer - Jul 31, 2018When adding a struct to a keyframe, Object Reference variables are not saved and Soft Reference variables are saved sometimes. Opening a keyframe's properties when the selected struct has an object ...
Crash caused by Buffer Overread in TBitArray operator < function
UE - Foundation - Core - Aug 29, 2018A licensee has reported a crash that is caused by a Buffer Overread in TBitArray's operator < function. While the licensee did not provide reproduction steps, the crash is apparent from looking at t ...
Crash on loading pre-4.20 cloth data when compute skin cache is enabled in 4.21
UE - Graphics Features - Mar 19, 2019According to information from the licensee, the else clause was added to "FSkeletalMeshLODModel::(GetClothMappingData()" at CL 4437969 , but if it is the cloth data existing from 4.20 or earlier, it ...
Compile on load crashes for classes within an abstract class
UE - Gameplay - Blueprint Compiler - Feb 20, 2021When compiling on load in -game, a blueprint class that inherits from a native class that is marked within and the class that it is within is abstract, a crash will occur when FBlueprintCompilationM ...
Incorrect volume bounds check in FTranslucentLightInjectionCollector::AddLightForInjection
UE - Graphics Features - Apr 8, 2025The 'VolumeBounds' array in FTranslucentLightInjectionCollector::AddLightForInjection is accessed as a pointer instead of with 'VolumeCascadeIndex' and thus fails bounds checks for the outer volume. ...
Setting Slate.ShowBatching to 1 makes the entire screen green unexpectedly
UE - AI Workflows - UI Systems - Slate - Jun 19, 2025This issue may have occurred due to a refactoring of the related functionality during the engine update from version 5.4 to 5.5. The main reason is that the randomization of BatchColor doesn't work ...
Blueprints with Input action events are dirtied and upon being opened
UE - Gameplay - Blueprint Editor - Aug 10, 2017Opening a blueprint that has an input event in it cause the blueprint to become dirtied and require compiling. Regression?: Yes This did not occur in 4.16.3-3561208+++UE4+Release-4.16 Versions tes ...
Level Sequence option "Allow Level Edits Only" causes Frame Rate drop when used
UE - Anim - Sequencer - Aug 15, 2017When using the new option "Allow Level Edits Only" there is a drastic frame rate drop while playing the sequencer. This frame rate drops when only using this option. Versions Tested: 4.16.3 - CL: 3 ...
Property Table rendering very slow in 4.19 (regression)
Tools - Feb 8, 2018Editor frame rate is very slow rendering the Property Table in 4.19. This is a regression from 4.18 Showing frame-rate in the editor with the property editor open shows really high GPU time: [Ima ...