Missing UV Clamping or Clear in SunAlphaPS_Mobile

UE - Platform - Mobile - Graphics - Nov 13, 2025

In: void SunAlphaPS_Mobile( float2 InUVs[8] : TEXCOORD0, in FStereoPSInput StereoInput, out HALF_TYPE OutColor : SV_Target0 ) { OutColor =  SunUnBias(SunShaftAndDofTexture.Sample(SunShaftAndDo ...

Gameplay Tags with the string "None" as any of its hierarchical node identifiers behave incorrectly (because of an incomplete generated FGameplayTagContainer::ParentTags array)

UE - Gameplay - Nov 19, 2024

Currently, using the string "None" as a hierarchical node identifier inside a Gameplay Tag (for example "A.B.C.None.D.E.F") is not disallowed by the engine, but results in some incorrect behaviors. ...

[CrashReport] UE4Editor_CoreUObject!UObjectBaseUtility::GetOutermost() [uobjectbaseutility.cpp:118]

Tools - Sep 8, 2016

This Jira was created from CrashReports submitted by the public due to the high number of occurrences. User DescriptionsSwitching levels, then when prompted to save current unsaved level, selecting ...

[CrashReport] UE4Editor_SlateCore!SWidget::SlatePrepass() [swidget.cpp:493]

Tools - Dec 1, 2017

This is a common crash in the 4.18 release. The callstack is rather generic, and I have attached two logs but neither displays the error information. Users have also not provided any descriptions ...

[CrashReport] UE4Editor_Engine!FShaderCompilingManager::LaunchWorker() [shadercompiler.cpp:1573]

UE - Graphics Features - Aug 21, 2017

This is a common and longstanding crash that has occurred since at least 4.9. The issue appears to be due to missing ShaderCompileWorker.exe in binaries, but many of these crashes occur in the vani ...

DataTable asset view runs out of (video) memory

UE - AI Workflows - UI Systems - Slate - Feb 26, 2024

In some situation, Slate tries to secure incredible amount size data and run out of memory. This happens a cell having very long and complex serialized text appears on the editor and it is placed to ...

Crash when manipulating Bone Space IK before setting EffectorSpaceBoneName

UE - Anim - Rigging - Feb 9, 2017

Error message: Assertion failed: Pose.IsValidIndex(BoneIndex) [Link Removed] [Line: 528] Source Context: 513 const FTransform& ParentTransform = GetComponentSpaceTransform(ParentIndex); ...

Translucent materials in the PostMotionBlur pass can cause a flickering viewport artefact when using TAA

UE - Rendering - Graphics Features - Feb 5, 2025

There appears to be a bug relating to rendering multiple windows that can trigger under unknown circumstances. It has been reported on rectangle lights in the forums and on PostMotionBlur materials ...

Properties not serialized when moving actor/component depending on unrelated specifiers

UE - Framework - Blueprint - Sep 25, 2023

When an actor is moved on the level editor viewport, it is reconstructed along with its components, which at first makes their properties reset to their default state. Thankfully, this does not happ ...

When using Subversion (SVN) and Lock's comment is Japanese outside SourceControl, parsing of xml fails and Status may become NotControlled.

UE - Foundation - Core - Jun 28, 2019

If user lock assets with Japanese comments outside source control, XML acquired in svn status may contain Japanese strings, and XML parsing may fail and become NotControlled. This issue does not oc ...