Niagara system loses source emitters when moving Engine from 4.22 or earlier to 4.23 or later.

UE - Niagara - Nov 29, 2019

The following code causes this behavior.// NiagaraSystem.cpp for (FNiagaraEmitterHandle& EmitterHandle : EmitterHandles) { EmitterHandle.ConditionalPostLoad(NiagaraVer); if (!EmitterHandl ...

Problems in skeletal mesh merge

UE - Editor - Content Pipeline - Asset Build - May 10, 2021

There are a few issues a licensee has found with the skeletal mesh merge operation. See the UDN for more details and the proposed fixes. Note, the issue with the cloth merge is already logged in a ...

[Submix][Content Browser] - Deleting an unsaved Submix asset (any type) causes them to reappear when creating a new asset

UE - Audio - Submixes - May 13, 2021

Deleting unsaved Submix assets causes them to reappear the next time you create a new asset. Issue does not occur in 4.26, but does occur in 4.27 and 5.0. ...

UMaterialBillboardComponent does not render when moving

UE - Graphics Features - May 19, 2022

Marking this as a Regression since it works as intended in Release 4.27.2 (CL-18319896). I've also confirmed the behavior is occurring in UE5 Main (CL-20283975) as well.  ...

bIgnoreAllPressedKeysUntilRelease only applies to keys in the previous mapping

UE - Gameplay - Input - Jun 16, 2022

This is because the RebuildControlMappings function only checks this flag when you have a mapping that was already added, we should apply this for any new mappings as well.  I'll update the repro s ...

Physics Constraint returns incorrect values for Swing1, Swing2, and Twist

UE - Simulation - Physics - Jul 7, 2022

Tested in //UE5/Main CL#20966071 Tested in //UE4/Release-4.27 CL#18319896 Physics Constraint returns incorrect values for Swing1, Swing2, and Twist. ...

Crash when changing shadow scalability settings to low, then clicking in the viewport

UE - Graphics Features - Jun 9, 2016

A crash occurs after setting the shadow scalabilty settings to "low" then clicking on an item in the viewport. The issue also occurs when setting all of the scalabilty settings to low at one time as ...

Geometry Material Alignment not functioning in 4.8

Tools - Jun 15, 2015

Material Alignment on BSPs are not functioning in 4.8.0 Release. This is a regression from 4.7.6. The issue does appear to be fixed and functional in 4.9 (Promotable-CL-2581018) ...

GameMode::StartNewPlayer calls RestartPlayer() without checking PlayerCanRestart()

UE - Gameplay - Nov 11, 2015

Bug report from UDN thread. https://udn.unrealengine.com/questions/266937/gamemodestartnewplayer-calls-restartplayer-without.html#answer-268579 His point seems sound, we should fix it. ...

[CrashReport] FBX import crash - UE4Editor_UnrealEd!TSet<TPair<unsigned int,FMeshSectionInfo>

Tools - Jan 12, 2017

This crash was introduced in 4.14.2, and is very similar to [Link Removed], however it is still occurring in 4.14.3 (after that fix) According to submitted crash reports, this one is not very wides ...