HandleKismetEvent (console cmd 'ke'): GT-ALT deadlock when user function flushes async loading

UE - Foundation - Core Systems - EditorLoader - Apr 8, 2026

Context In builds with the in-game console enabled, users can use the ‘ke’ command to execute UFUNCTIONS on any object:ke * MyFunc // run MyFunc() on ANY UObject with a ufunction with that name ke ...

Material parameters flickering due to UMG animation switching and multi-threaded execution

UE - Editor - UI Systems - UMG - May 12, 2026

When continuously transitioning to UMG animations that have a track targeting the same material parameter within the UUserWidget::OnAnimationFinished event, the number of source inputs to UMovieScen ...

[CrashReport] PhysX3PROFILE_x64!physx::Sc::BodySim::activateInteractions() [scbodysim.cpp:496]

UE - Simulation - Physics - Jul 19, 2017

This is a common crash affecting users in 4.16. The callstack is very similar to [Link Removed], which has previously been fixed. User DescriptionsTesting destruction of generated destructables. T ...

ISequencer::OnPlayEvent does NOT fire at the end of playback in Sequencer editor

UE - Anim - Sequencer - Jul 8, 2022

ISequencer :: OnStopEvent is executed when pause, but not when playing to the last frame and stopping automatically. This is because OnStopDelegate.Broadcast(); is only in FSequencer::Pause(). When ...

Static/stationary child actor components are invisible and/or move position when placed inside a dynamically loaded level

UE - Framework - Components - Oct 31, 2024

When loading a non-world partitioned level into a persistent world partitioned level, parent actors with child actor components within the loaded map will move position or become invisible. Within t ...

[CrashReport] UE4Editor_Sequencer!TBaseMulticastDelegate<void>::RemoveDelegateInstance() [delegatesignatureimpl.inl:964]

UE - Anim - Sequencer - Oct 5, 2017

This is a slightly common crash coming out of the 4.17.2 hotfix. Users have not provided any descriptions of their actions when the crash occurred. Source Context 951 /** 952 * ...

Make literal container nodes (e.g. MakeArray) do not cast object ref output terms linked to interface-typed input pins.

UE - Framework - Blueprint - Jan 28, 2023

As with most nodes, object reference outputs can be directly connected to interface-typed inputs on "make container" nodes (e.g. "MakeArray") if the object's class type implements the interface clas ...

Dangling pointer + mem corruption related to OwnerLastRenderTimePtr

UE - World Creation - Worldbuilding Tools - Mar 16, 2026

We've been seeing asserts and crashes related to OwnerLastRenderTimePtr. We've traced this to the mentioned pointer ending up dangling after using UActorComponent::Rename() on primitive components t ...

EDITOR: High Resolution Screenshot: Unable to capture high res shots in game or during cinematics

Tools - Sep 2, 2014

BRANCH: //depot/UE4/Promotable-CL-2281016 CHANGELIST: 2281016 BUILD TYPE: P4 PLATFORM: Windows FREQUENCY: 3/3 DESCRIPTION: Unable to capture High Res shots in game or during cinematics REPRO STEPS: ...

Crash when enabling dynamic branch on static switches in Post Process Materials

UE - Rendering - Architecture - Materials - Jun 28, 2023

[Link Removed] Some functions to access parameters don't take into account the newly added runtime static switch parameters. It should be straightforward to fix these up: void UMaterialInstance:: ...