When using Perforce, saving a level over another leaves the target umap file as "marked for delete"

UE - Editor - Mar 11, 2025

When working on a level asset and using command "File – Save Current Level As..." to save it over a different level asset, the engine first deletes the target level (that's going to be overwritten) ...

Division by zero in FAnimNode_StrideWarping::EvaluateSkeletalControl_AnyThread

UE - MVF Character - Animation - Sep 29, 2025

When an Actor's CustomTimeDilation is 0.0, functions FActorTickFunction::ExecuteTick() and FActorComponentTickFunction::ExecuteTickHelper() will call AActor::TickActor() and UActorComponent::TickCom ...

Dirty Actors in WP lose their actor folder in the outliner (and cause warnings) on PIE

UE - Engine Scaling - Streaming - World Partition - Mar 20, 2023

From Licensee: You can reproduce this in stock by doing the following:Make a new 5.1 project with a new WP map (it can be empty)Put some actors in some folders in the outliner and save them/reload ...

World Source in Take Recorder does not record auto-tracked actors properly

zComponent - Archive - May 23, 2025

The Take Recorder plugin allows for multiple sources to be recorded during gameplay. The World Source is expected to record everything in the level when the Autotrack Actors option is enabled. Once ...

Linux Crash Reporter can fail due to exceeding crash malloc space when generating the report

UE - Platform - Linux - Sep 16, 2026

On Linux a crashing process can fail to produce a crash report at all. The crash folder is created and contains CrashContext.runtime-xml and Diagnostics.txt, but the copied log file is 0 bytes, Cras ...

Crash on iOS9 when using Apple's CFNetwork library

UE - Platform - Mobile - Dec 6, 2016

Many clients have hit a crash due to an Apple library using operator delete on a memory block that was not allocated with operator new. This happens with the following callstack on iOS9 in UE4.13 o ...

Issue with importing alembic files: the skeletal mesh asset doesn't contain LOD description

UE - Editor - Open File Formats - Sep 15, 2026

Helloo everyone!! 😄 We are experiencing an issue with importing skeletal meshes from alembic. For reference, this issue happens in vanilla engine 5.7.4, but it doesn't occur in versions 5.6.x. 1) ...

If using SetAlignmentInViewport in Construct, the value with it is ignored

UE - AI Workflows - UI Systems - UMG - Jan 27, 2023

If SetAlignmentInViewport is called in the UMG Construct, it is ignored internally. This is due to a change that came in 5.1, so it worked fine in 5.0. First, when the Set Alignment in Viewport nod ...

iOS Metal-based build crashes at launch with sub-levels.

Tools - May 16, 2016

Application crashes when deploying a game to iOS with Metal enabled. This has only been reproduced if a sub-level has been added to the starting level within the project. This seems to only happen ...

Search field in 'Quickly Add to Project' fails with Chinese Pinyin input unless manually focused

UE - AI Workflows - UI Systems - Localization - May 28, 2025

A licensee reported that under the Chinese language setting in UE5, using the “Quickly Add to Project” button results in incorrect or ignored input when entering text via Pinyin IME. If the user sta ...