Linux crashes in the Project Browser without using the -nocef command

UE - Platform - Linux - Feb 22, 2022

When opening Unreal Editor on Linux, the Project Browser opens but is completely unresponsive. Shortly afterwards the editor will crash. If you use the -nocef command when opening the Editor, everyt ...

ResavePackages commandlet (buildlighting) fails/asserts on reflection captures in non-visible sub-levels

UE - Rendering - Graphics Features - May 13, 2025

When building reflection captures through the ResavePackages commandlet, it frequently triggers an ensure inside of ReflectionEnvironmentCapture.cpp. If distributed shader builds start causing prob ...

Changing the ComponentClass of a ACharacter twice and trying to set a SkeletalMeshAsset crashes the engine

UE - Anim - Jan 22, 2026

Changing the ComponentClass of a ACharacter twice and trying to set a SkeletalMeshAsset crashes the engine with a "Cannot replace existing object of a different class" message. The conditions to re ...

[CrashReport] Access Violation - UModelComponent::GetPhysicsTriMeshData() [modelcomponent.cpp:673]

UE - Simulation - Physics - Oct 2, 2017

This is a trending crash coming out of the 4.18 Previews. Users have not provided any descriptions of their actions when the crash occurred. The callstack is similar to [Link Removed], which was ju ...

Structs cause packaging to fail when Blueprint Nativization Method is set to "Inclusive"

UE - Gameplay - Blueprint - Apr 26, 2017

Structs cause packaging to fail when Blueprint Nativization Method is set to "Inclusive" Note: Appears to be a regression (worked in 4.15.1) Error example: UATHelper: Packaging (Windows (64-bit)) ...

Unreal Insights - GPU Timers don't show on Graph

UE - Foundation - Insights - Oct 27, 2023

From Customer: UE 5.3 update broke Unreal Insights adding GPU timers into graph tracks. Debugging the code and cross checking with github/p4v I guess it broke in this revision: Timer graphs no ...

[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 ...

Property Editors fail to import text values for FKeys within array/set/map containers when the key is identified by some valid non-alphanumeric characters

UE - Gameplay - Input - Oct 28, 2024

The FKey structure represents a user action input such as a keyboard key, a mouse button/wheel, or a gesture in VR. For the keyboard, it can represent any pressable key, such as letters, numbers, sy ...

Changing the state of a PrimitiveComponent->BodyInstance while SetSimulatePhysics(false) updates the game thread but does not update the physics behavior

UE - Simulation - Core - Nov 21, 2024

Changing the state of a PrimitiveComponent->BodyInstance while SetSimulatePhysics(false) updates the game thread but does not update the physics behavior. In the repro project provided (see addl in ...