Unreal Engine Issues
Unreal Engine Issues
Consistent Crash using Cinematic Viewport on Linux
UE - ACT Character - Sequencer - Aug 13, 2026We are getting multiple crashes on 5.8.1 when trying to use the cinematic viewport on Linux, the most consistent way it's been reproduced is by clicking on the blue frame number to the left of the c ...
[MetaSounds] - Changing an Input to Modulation Parameter crashes editor due to module load order
UE - Audio - MetaSounds - May 27, 2022Setting an Input type on Modulation Parameter crashes the editor with:Assertion failed: Pair != nullptr [File:E:\SMoyls_UE5_Release-5.0\Engine\Source\Runtime\Core\Public\Containers\Map.h] [Line: 643 ...
Emissive material lighting falloff regression in GPU Lightmass
UE - Rendering - Features - Sep 12, 2023Forum user noted that emissive lighting being built with GPU Lightmass is in fact being built, just not around the mesh, but in a larger radius and with reduced strength compared to 5.1.1. They foun ...
"Too many texture coordinate sets" warnings in KiteDemo
UE - Graphics Features - Jan 17, 2017Full set of warnings:LogShaderCompilers:Warning: Failed to compile Material /Game/KiteDemo/Environments/Trees/HillTree_02/HillTree_01_Leaves_Mat.HillTree_01_Leaves_Mat for platform PCD3D_SM5, Defaul ...
Misspellings in Material_Properties level of ContentExamples
Docs - Samples - Jan 18, 2017In the Material_Properties level of ContentExamples, separate is misspelled in demo display 1.6 and tessellation is misspelled in demo display 1.8. ...
Bake To Control Rig on a Spawned Actor in a Subsequence with Play Range that exceeds the Subsequence causes a Crash
UE - ACT Character - Anim in Engine - Jun 28, 2023This is a Regression. Tested in //UE5/Release-5.1 CL23901901 Using Bake To Control Rig on a Spawned Actor in a Subsequence with Play Range that exceeds the Subsequence causes a Crash. ...
[CrashReport] Commandlet crash - UE4Editor_Engine!FAnimationUtils::CompressAnimSequenceExplicit() [animationutils.cpp:621]
OLD - Anim - Sep 7, 2017This is an infrequent commandlet crash that has affected a number of users exclusively in 4.17.1 (possible regression from 4.17.0?). There are also two instances of older cases in 4.13 and 4.15, bu ...
Transform Origin Scale on the Level Sequencce Actor's Instance Data can affect rotations
zComponent - Archive - Apr 30, 2025Scale is used as part of the rotation calculation for transform multiplication, and it can have an effect in the sequence transform origins. It's expected that scale is completely ignored, and shou ...
"Build All Levels" does not re-AddNavigationSystemToWorld
UE - Runtime - Character - Feb 28, 2024The Build All Levels editor action cleans up the world's NavDataSet (UNavigationSystemV1::NavDataSet) as pre-rebuild world cleanup by calling: SetNavigationSystem(nullptr); inside UWorld::Cleanu ...
FString.Mid doesn't react appropriately when given negative values for the Count variable
UE - Foundation - Core - Jul 16, 2015If you use a 5 character string (hello) to call the Mid function and provide 0 for start, -1 for count, it'll give you the entire string. This should either return an assert or treat all negatives a ...