Unreal Engine Issues
Unreal Engine Issues
Custom Primitive Data on BP instance not taking affect while in editor
UE - Rendering - Architecture - Apr 5, 2023Original Repo is from 4.27, however, it still happens in 5.2. This is happening because the Instance Data system does not update the field UPrimitiveComponent::CustomPrimitiveDataInternal from the d ...
[Enhanced Input] Edge case where bShouldBeIgnored incorrectly being reset after FlushPressedKeys is called
UE - Gameplay - Input - Apr 2, 2026[Link Removed] From UDN, the steps for their repro case: Normal case: Frame N : AddMappingContext → bShouldBeIgnored=true → FlushPressedKeys → bDown=false Frame N+1: OS IE_Repeat arrives → ...
[CrashReport] UE4Editor_Slate!FSlateApplication::RoutePointerMoveEvent() [slateapplication.cpp:5195]
UE - Editor - UI Systems - Slate - Jun 28, 2017This is a longstanding crash that occurs with low frequency, but has affected over 200 users. One user describes that this occurred while packaging a project, although other users have not provided ...
GetPackageLengthForCooking can be much larger than the actual file path length
Tools - Jul 10, 2019If the file path with the asset contains a project name, the cooking file pathlength is incorrectly increased. The following code in ContentBrowserUtils :: GetPackageLengthForCooking causes this is ...
Access Violation - UMovieSceneFolder::PostLoad - Accessing freed memory
UE - Anim - Sequencer - Sep 19, 2024A licensee has hit an access violation issue due to a movie scene containing a reference to an invalid child object binding. It triggers in the following method: UMovieSceneFolder::PostLoad // Vali ...
[CrashReport] UE4Editor_Persona!<lambda_e529d88d0657fbede17be1535bc6d479>::operator() [blendspacedetails.cpp:29]
OLD - Anim - Aug 14, 2017This is a trending crash coming out of the 4.17 release. Users have not provided any descriptions of their actions when the crash occurred. The callstack is very close to https://jira.it.epicgames ...
Player Controller does not handle multiple CharacterMovement movement modes
UE - Gameplay - Blueprint - Feb 6, 2018From Bug Submission: The variable in the image I attached is unable to distinguish between multiple characters all possessed by the same player controller. So if one character has this variable set ...
When asynchronously loading levels using the "Async Load Primary Asset" node, the dirty flag of the loaded level becomes Enable
UE - Gameplay - Jul 26, 2018Asynchronously loading a level that has one or more Actors using the "Async Load Primary Asset" node will enable dirty grug for that level asset. The cause is a modified code(CL-3764602) for the [L ...
Unreal Insights - GPU Timers don't show on Graph
UE - Foundation - Insights - Oct 27, 2023From Customer: UE 5.3 update broke Unreal Insights adding GPU timers into graph tracks. Debugging the code and cross checking with github/p4v I guess it broke in this revision: Timer graphs no ...
DynamicMaterialParameters Niagara module resets write flags on emitter update
UE - Niagara - Feb 4, 2026When using the DynamicMaterialParameters Niagara module in UE 5.6, 5.7, and UE5-Main (CL 50298778), updating an emitter causes Boolean values, such as Index0Float0Write, to reset to default values, ...