Composite font uses a sub-font, even when the sub-font doesn't support the character

Tools - Apr 7, 2016

I have a fix for this shelved in CL# 2937344, so it would be good to get it into 4.12 once the user verifies the fix. ...

MotionWarping does not recognize new MontageInstance with the same montage

UE - Anim - Gameplay - Jan 11, 2023

When the same AnimMonotage is played again while moving with MotionWarping & RootMotion, UAnimNotifyState_MotionWarping does not recognize it. From licensee: The issue was that in URootMotionMod ...

[CrashReport] Linux_PlatformCreateDummyGLWindow()

UE - Platform - Linux - Nov 16, 2017

This is a trending Linux crash in the 4.18 release Callstack from Log[2017.11.10-14.42.41:021][ 0]LogLinux: Error: appError called: Assertion failed: [File:/media/***/OS/UnrealEngine-release/Engi ...

UAssetManager::ChangeBundleStateForPrimaryAssets: Performance: Avoid canceling loads in progress when new bundles added and the in progress bundles are kept

UE - Foundation - Data Pipeline - Cooker - Mar 4, 2024

UAssetManager::ChangeBundleStateForPrimaryAssets allows adding new BundleNames to the list of BundleNames loaded for a PrimaryAssetId. Each BundleName specifies a BundleEntry with a list of assets. ...

Sequencer - When a subsection has negative play rate, any nested sub-subsections fail to evaluate

UE - Anim - Sequencer - Jul 3, 2025

Consider a sequence hierarchy with more than two layers. If the top-level sequence uses a negative timescale on a sub-sequence, the contents inside it animate as expected, but any nested sub-sequenc ...

[CrashReport] ULevel::GetWorldSettings - UMaterialFunctionThumbnailRenderer::Draw

Tools - Oct 30, 2017

This is a common crash that has occurred since at least 4.16. The callstack is nearly identical to [Link Removed], which appears to be fixed in 4.18; and [Link Removed], which has not. The differen ...

Unknown force is applied to the cloth when changing the skeletal mesh LoD with cloth.

UE - Simulation - Physics - Character - Jul 11, 2019

There are 3 issuesEach particles don't restore its previous position. Which is for calculating velocity by verlet iteration.The previous transform is cleared by current transform. It provides zero v ...

[CrashReport] UE4Editor-Slate.dylib!FMenuStack::PostPush(TSharedPtr<IMenu, (ESPMode)0>, TSharedRef<FMenuBase,()

Tools - Dec 1, 2017

This is a longstanding but infrequent Mac crash that has occurred since at least 4.15. Users have not provided any descriptions. Callstack from Log[2017.11.19-04.18.41:283][ 0]LogSlate: Took 0.000 ...

MovieRender Pipeline Skips Output Frames during GC

UE - Anim - Sequencer - Jun 8, 2020

This is being seen in the wild... can release a temporary fix until 4.26 when we can change the headers and fix it for real. ...

Reintroduce UE4 Material Layer drag & drop behavior in UE5

UE - Rendering Architecture - Materials - Oct 19, 2023

This behavior has changed from UE4 to UE5 due to a fix to an unrelated bug ([Link Removed]). Reintroduce the old behavior without causing a regression that reintroduces Ben's fixed bug. ...