FNiagaraScalabilityManager incorrectly reactivates a NiagaraComponent that was deactivated by runtime user code

UE - Rendering - Architecture - Niagara - Oct 1, 2025

Context: The Niagara System is the primary tool to do visual effects inside Unreal. Niagara systems can be culled due to distance. Problem: Once a deactivated Niagara System is culled due to distan ...

LevelSequenceActorSpawner::GetLevelStreaming() fails to compare sub level names when running in Pie

UE - Anim - Sequencer - Sep 26, 2019

The problem is in the function with signature "ULevelStreaming* GetLevelStreaming(FString SafeLevelName, UWorld& World)" within LevelSequenceActorSpawner.cpp at line 30. The problem is with the Safe ...

(Linux) - Editor crashes out when any change in project files

UE - Rendering - RHI - Oct 23, 2026

POST LINK: https://forums.unrealengine.com/t/linux-editor-crashes-out-when-any-change-in-project-files/2733237 POST BODY:Summary Ue 5.8 Fresh install and basically fresh project. Any time Ue detec ...

Reversed Animations don't play properly using Skeletal Mesh Pose and animations with Keep State in Sequencer

UE - Anim - Sequencer - Nov 26, 2018

The bug seems to only reproduce when setting animations in sequencer and only if the animations are set to "Keep state". Setting them to "restore default" makes the reversed animation play correctly ...

Physics Asset details window jitters when shrunk.

Tools - Sep 29, 2014

Branch Build Label UE4-Main Promoted-CL- 2306964 DESCRIPTION: When using the vehicle template and having any wheel selected inside the physics asset, shrinking the size of the details window ca ...

Crash adding an AnimComposite to itself

OLD - Anim - Feb 24, 2017

Error message: Stack overflow - code c00000fd (first/second chance not available) Source Context: 74 void UAnimComposite::GetAnimationPose(FCompactPose& OutPose, FBlendedCurve& OutCurve, c ...

Creating a copy of BSP after fliping it in geometry edit mode cause the copy to be invisible

UE - LD & Modeling - Modeling Tools - BSP - Aug 29, 2014

Branch Build Label UE4-Main Promoted-CL- 2270796 DESCRIPTION: If a player goes into geometry edit mode and flips a bsp then makes a copy of it the copy will appear invisible ADDITIONAL NOTES: A ...

[CrashReport] UE4Editor_Engine!FAnimCurveBase::SetCurveTypeFlag() [animcurvetypes.cpp:18]

OLD - Anim - Jun 13, 2016

This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Descriptions from users are provided below. Error message: Access violation - code c0000005 ( ...

[CrashReport] UE4Editor_AlembicLibrary!AbcImporterUtilities::GenerateSmoothingGroupsIndices()

UE - Gameplay - Aug 5, 2016

This JIRA is being entered as a result of it being one of the top crashes occurring in 4.13 Preview 1. Error message: Assertion failed: (Index >= 0) & (Index < ArrayNum) [Link Removed] [Line: 833] ...

Crash when quick binding a function in a class that extends LevelSequenceDirector

UE - Anim - Sequencer - Sep 16, 2020

The purpose was to create a Level Sequence Director inheritance class so that the same event could be reused in multiple sequencers. Attempting to quick-bind this base Level Sequence Director event ...