Unreal Engine Issues
Unreal Engine Issues
Widgets will bind input delegates to the Player Controller's Input Component, but never unbind them
UE - Editor - UI Systems - UMG - Jan 30, 2024This is a bug introduced with 18468289 a while ago. We added this functionality for [Link Removed], which allows input event nodes to be placed within widgets and have them behave correctly. This ...
LineTraceSingleByChannel does not correctly use the collision response set for the channel being traced on
UE - Simulation - Physics - Nov 28, 2017There appears to be an issue with how raycasts are performed within PxScene. When performing the trace, only the collision response for the first ECollisionChannel seems to be considered. If all col ...
Setting a struct bool property (bitfield) to itself writes the wrong value
UE - Framework - Blueprint Compiler - Sep 17, 2025There's an issue when assigning a bitfield bool to a native bool in Blueprints. Currently, the engine erroneously treats the memory for a local bool as a uint8 bitfield, which is undefined behavior. ...
[CrashReport] UE4Editor_Engine!FPointerToUberGraphFrame::~FPointerToUberGraphFrame()
UE - Gameplay - Blueprint - Aug 15, 2017This is a trending crash coming out of the 4.17.0 release. Users have not provided any descriptions of their actions when the crash occurred, however the callstack is very similar to [Link Removed] ...
[CrashReport] UE4Editor_Landscape!FLandscapeComponentSceneProxy::FLandscapeComponentSceneProxy() [landscaperender.cpp:680]
UE - LD & Modeling - Terrain - Landscape - Apr 11, 2018User comment in crash group:Wanted to delete a single field of my landscape wich is very big. Same error appears if I try to get a part of the landscape to another streaming level. Would be cool if ...
CheckCompilingPSOs assert in FMaterialPSORequestManager::MarkCompilationComplete fires occasionally
Find the root cause and fix it. Potential issue based on logs:New RequestA is created in PrecachePSOs and its collection task is dispatched and finishedRequestA is waiting for compilation taskReque ...
Undo/Redo can cause the gizmo to desync from a leaf-selected component
UE - Editor - Workflow Systems - Oct 18, 2021This is a regression from 4.27. This is happening because of the change to typed elements. UEditorEngine::PostUndo, when combined with the typed element changes causes the selection set to reorder ...
AbilityTask_PlayMontage will 'zombie' if Interrupted during BlendOut
UE - Gameplay - Gameplay Ability System - Apr 14, 2023User reports: I've noticed a bug with PlayMontageAndWait There are 4 possible triggers when a Montage completes:OnCompletedOnBlendOutOnInterruptedOnCancelled Once OnBlendout has been triggere ...
Orphaned BP actors when using UWorldPartitionBuilder
UE - World Creation - Worldbuilding Tools - World Partition - Nov 21, 2025From an EPS case: --------------------------------- We're seeing a recurring issue where child BP actors are becoming orphaned during any processing that uses UWorldPartitionBuilder. It affects ...
Editor crashes when changing skeletal mesh if another skeletal mesh component is attached when using master pose node
OLD - Anim - Jan 27, 2020The crash only occurs if the additional skeletal mesh component is used with Set Master Pose Component (see ToggleAttach function in the TopDownCharacter BP). It doesn't seem to matter what mesh we' ...