Crash when trimming animation and then undoing action

UE - Anim - Runtime - May 30, 2023

Repro rate: 3/3 times This is a regression as the issue does not occur in 5.1.1  ...

Exception on missing fiile during GC in horde storage

UE - Foundation - Horde - Storage - May 7, 2025

During GC, if a file was manually deleted (but the storage system is still track), GC can erroneously fail (and never remove the reference). This causes a backup in GC, putting the whole algorithm i ...

Crash occur package application which set the StringTable

UE - Foundation - Core - Mar 14, 2019

Crash occur the packaging application which has the title referencing StringTablem. When lunch the application with editor and standalone, it's not crash. It' not occur 4.20, and crash with 4.21 and ...

Some Niagara FX does not show up in MovieSceneCapture when AgeUpdateMode is DesiredAgeNoSeek

UE - Niagara - Cinematics - Sep 17, 2024

CL23957356 changes how to calculate FrameOffset in FNiagaraSystemUpdateDesiredAgeExecutionToken::Execute(). After this change, DesiredAge + FrameOffset could be 0.0 for some a couple of initial fram ...

[CrashReport] UE4Editor_MaterialEditor!FMaterialEditor::GetToolkitName() materialeditor.cpp:820

UE - Rendering Architecture - Materials - Nov 21, 2017

This is a new crash coming out of the 4.18.1 hotfix. There is no record of it previously occurring, so it is possible it may be a regression. Users have not provided any descriptions of their actio ...

[CrashReport] UE4Editor-TargetDeviceServices.dylib!TRawMessageHandler<FTargetDeviceServicePong, FTargetDeviceProxyManager>::HandleMessage(TSharedRef<IMessageContext,()

UE - Platform - Apple - Oct 5, 2017

This is a slightly common Mac crash that has occurred since 4.17.1. Users have not provided any descriptions of their actions when the crash occurred. Callstack from Log[2017.09.28-15.29.17:473][3 ...

Sequencer frame range progression is not continuous

UE - Anim - Sequencer - Oct 28, 2021

The end of the level visibility section places a DeterminismFence. This causes the issue. The fence clips the frame range and produces a discontinuous frame ranges, e.g. 23201~24000, then 24001~24 ...

Unloading level during PIE leads to editor crash

Tools - Dec 6, 2017

Unloading level during PIE seems to lead to an editor crash. Most easily reproducible by enabling malloc stomp. ...

For a TMap with C++ enum keys, deleting and re-adding a map entry in the Editor can corrupt the map data.

UE - Editor - Workflow Systems - Jul 19, 2024

When adding an entry to a TMap using UE's property editors, in most cases the new entry comes with a default-initialized key (if such key already exists, the insertion fails). The case of a UENUM de ...

[CrashReport] Mac crash - FCocoaRunLoopSource::Process

UE - Platform - Apple - Sep 14, 2017

This is a somewhat common Mac crash that has occurred since at least 4.14 and into 4.17. Users have not provided any descriptions of their actions when the crash occurred. The callstack contains l ...