Construction script does not properly reset array count

UE - Gameplay - Oct 28, 2019

It appears that in UE 4.23, some specific arrays in construction scripts are no longer cleared automatically and retain references to TRASH objects from the previous construction script calls. This ...

WildCard Inputs/Outputs Propogate Incorrectly in Macros

UE - Gameplay - Dec 13, 2019

When a macro takes in a two Wildcard inputs and two Wildcard outputs connecting a variable to one assigns the value of all the outputs even if they don't connect (check attached image). You can see ...

Reimporting of skeletal mesh results in a scrambled skeletal mesh

UE - Editor - Content Pipeline - Import and Export - Oct 17, 2025

When we reimport our skeletal meshes with updated FBXs, the resulting skeletal mesh is scrambled up. See Scrambled.jpg attached. This does not affect every single reimport but happens randomly. W ...

FDetailGroup::AddGroup does not correctly apply the default expansion state for DetailGroups

UE - Editor - Verse Class Editor - Feb 10, 2026

There is a bug affecting DetailGroups in the engine. When adding child DetailGroups to a parent DetailGroup, the expansion state does not behave as expected and ignores the flags intended to control ...

Fixing up GoogleVRHMD static analysis warning

UE - Platform - XR - Oct 31, 2016

[Line 1585] d:​\build​++ue4+release-4.14+compile​\sync​\engine​\plugins​\runtime​\googlevr​\googlevrhmd​\source​\googlevrhmd​\private​\googlevrhmdrender.cpp(42) : warning C6386: Buffer overrun while ...

[CrashReport] UE4Editor_UnrealEd!UnFbx::FFbxImporter::RecursiveBuildSkeleton()

UE - Editor - Content Pipeline - Import and Export - Jul 30, 2015

This is a common crash affecting users. User DescriptionsJust import a Mesh of Fuse Source Context 624 void UnFbx::FFbxImporter::RecursiveBuildSkeleton(FbxNode* Link, TArray<FbxNode*>& Out ...

[CrashReport] UE4Editor_Sequencer!FSequencer::NotifyMovieSceneDataChanged()

UE - Anim - Sequencer - Jul 24, 2017

This is a common crash affecting users in 4.16 and into the 4.17 Preview. User Descriptionscopying-pasting curves in Sequencer Source Context 979 void FSequencer::NotifyMovieSceneDataCha ...

Source Won't Build - UnrealInsightsCLI.cpp References Missing Header

UE - Foundation - Core - May 11, 2020

Line 9 in https://github.com/EpicGames/UnrealEngine/blob/4.25/Engine/Source/Programs/UnrealInsightsCLI/Private/UnrealInsightsCLI.cpp is '#include "TraceServices/SessionService.h" which used to be lo ...

Actors are not properly restored when undoing a Replace Selected Actors transaction

UE - Gameplay - Components - Jul 22, 2020

When undoing a Replace Selected Actors operation, the resulting actor is corrupt and triggers an ensure where the root component is in the process of being destroyed. This is a regression that poppe ...

Cloth Rendering - Optimizations cause a one frame geometry stretch when off screen cloth is teleported back on screen.

UE - Runtime - Simulation - Aug 26, 2021

Render optimizations are causing the cloth render data to be updated one frame too late after an off screen cloth object has been teleported back on screen. The optimisation triggers itself after a ...