Alt-tabbing out of a Standalone App or packaged version of a game does not trigger LostFocus or ReceiveFocus

Tools - Sep 9, 2015

If a user uses Alt-tab to change to another window, the ReceivedFocus and LostFocus functions are not called as they would usually be called when using something such as Shift+F1 or Ctrl+Esc. Note: ...

Blueprints not marked dirty when variables in referenced actors are renamed

UE - Gameplay - Blueprint Compiler - Feb 20, 2018

Blueprints using renamed variable do not indicate that they need to be recompiled. (However errors are shown on play) It is possible to not see an error if you add a variable with the same name as ...

Crash on Importing specific Animation Only FBX

Tools - Nov 16, 2015

When importing the attached FBX file with only Animations, the editor will crash. The Same asset will import without error in 4.9.2 Crash Reporter BUGG: [Link Removed] ...

Crash when spawning destructible objects in 2 player PIE

UE - Simulation - Physics - Destruction - Aug 31, 2016

Crash Reporter link: [Link Removed] With Source Context: [Link Removed] ...

OnComponentWake Event does not trigger when the physical body is awoken by a Force

UE - Runtime - Simulation - Feb 27, 2025

OnComponentWake Event does not trigger when the physical body is awoken by a Force. The steps described on Steps To Reproduce is enough to replicate this behavior. The OnComponentWake event is only ...

Interchange Runtime .glb Import Crash When Packaged

UE - Editor - Content Pipeline - glTF - Jun 10, 2025

The runtime import process works fine in editor, but fatal error when trying to do so with packaged build of project. My function that calls ImportAsset():bool UMeshLoader::RequestMeshLoad(FString ...

Crash during shader compilation when r.Shaders.Optimize=0

UE - Rendering - Architecture - Shaders - Mar 11, 2024

The primary shader crashing is "FVisualizeLumenSceneCS" which I've put in the callstack section, but I think this is more likely a binding problem as I'm also see the following crash with cloud shad ...

A Skeletal Mesh simulating physics that hits a Geometry Collection Actor with OneWayInteraction true, OneWayInteractionLevel 1, and is using Damage Propagation (default) will be accelerated so fast it immediately disappears by hitting the world limits

UE - Runtime - Simulation - Jan 20, 2025

A Skeletal Mesh simulating physics that hits a Geometry Collection Actor with OneWayInteraction true, OneWayInteractionLevel 1, and is using Damage Propagation (default) will be accelerated so fast ...

Crash Occurs When Creating Pose Asset from an Animation in Persona

OLD - Anim - Feb 1, 2018

Engine crashes when creating a new pose asset in persona using the Create Asset option -Tested with walk, idle, and run anims -Didn't crash only once out of the several times tested with the Third ...