TMap<Bool is disallowed despite bool having a hash

UE - Gameplay - Blueprint - Nov 22, 2022

Reproduced 3/3 times. User is unable to create a new TMap with bool key through Blueprints (which is the expected result).  Issue is technically a Regression, as the ensure does not occur in //UE5/ ...

FileSystemDerivedDataBackend may output a corrupted access log

UE - Foundation - Core - Derived Data - May 20, 2021

This problem is caused by the AccessLogWriter has not been flushed at the termination. The following workaround flushes the Writer.class FFileSystemDerivedDataBackend : public FDerivedDataBackendInt ...

Attaching New Camera Actor to Spring Arm Component does not set the Location Correctly

UE - Gameplay - Blueprint - Apr 2, 2015

After adding a new Camera Actor Component within Blueprints to an existing Spring Arm Component, the Camera Component adopts the location settings , but does not set its location within the viewport ...

Editing an instanced variable that is nested in two other instanced variables causes a crash

UE - Gameplay - Blueprint - Jul 2, 2015

If a user edits a instanced variable which is nested inside two other instanced variables in blueprint editor, a crash will occur ...

Behavior of Speed Up/Down parameter of Auto Exposure are different.

UE - Graphics Features - Apr 5, 2016

Brend/Swtch multi PostProcessVolume to handle Auto Exposure with same Speed Up/Down parameter but behavior of Speed Up/Down parameter of Auto Exposure are different. Scene with. Unbounded PostProce ...

Landscape has a seam when scale is set to a decimal

UE - Graphics Tools - Terrain - Landscape - Jan 13, 2023

Regression: Tested in UE5/Release-5.0 at CL 20979098, this issue does occur so it is not a regression. This issue occurs if the scale set for the landscape has a decimal value that is not 0.5. Sett ...

[CrashReport] UE4Editor_HeadMountedDisplay!FDefaultSpectatorScreenController::Helpers::GetEyeCroppedToFitRect() [defaultspectatorscreencontroller.cpp:363]

UE - Platform - XR - Nov 10, 2017

This is a trending crash coming out of the 4.18 release. It has also been experienced internally by QA. User DescriptionsUEQA-Juliet Talcott - minimizing Source Context 352 // Eye rect is t ...

Cull Distance Volumes do not effect Blueprints or Skeletal Mesh Actors

UE - Graphics Features - Jul 31, 2014

CHANGELIST: 2181118 BRANCH: UE4 https://udn.unrealengine.com/questions/166371/cull-distance-volume-bug.html DESCRIPTION: Cull distance volumes don't seem to cull blueprints or meshes inside a bluep ...

Physics Constraint Actor: When plasticity is enabled, Drive Position Target is reset to zero on constraint initialization

UE - Simulation - Core - Mar 5, 2026

When a Chaos joint constraint is first created, having linear/angular plasticity enabled will unexpectedly force its linear/angular drive position target to zero on initialization, disregarding the ...

[CrashReport] UE4Editor_MeshPaint!FMeshPaintGeometryAdapterForStaticMeshes::OnRemoved() [meshpaintstaticmeshadapter.cpp:222]

Tools - Nov 21, 2017

This is an infrequent crash in the 4.18 release. Users have not provided any description of their actions when the crash occurred. Source Context 210 if (StaticMeshReferencers) 211 ...