[CrashReport] UE4Editor_Engine!USplineMeshComponent::CalculateScaleZAndMinZ()

Tools - Jun 27, 2017

This is a common crash occurring in the 4.16 release. It has occurred for many users, but nearly every user's project is named some variation of "pinball", this makes me wonder if the repro is surf ...

Current animation asset is lost in animation preview when a post process anim BP is compiled

UE - Anim - Runtime - Anim Blueprints - Aug 3, 2020

UDebugSkelMeshComponent and PreviewInstance are lost current animation asset. There are 2 ways to fix below void UDebugSkelMeshComponent::InitAnim(bool bForceReinit) { // If we already have Pre ...

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

zComponent - Archive - 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 - Engine Scaling - Streaming - 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 ...

FStateTreeExecutionContext::GetDebugInfoString() outputs wrong info and crashes when using linked state trees

UE - AI - Debugging - Apr 17, 2025

When using State Trees, the AI Debugger can be accessed during play to show information about their current execution state. If a behavior tree is currently in a state that references a linked tree, ...

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 - Engine Scaling - Streaming - 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 ...

[CrashReport] UE4Editor_Engine!FPhysScene::SyncComponentsToBodies_AssumesLocked() [physscene.cpp:1271]

UE - Simulation - Physics - Dec 1, 2017

This is a common crash in 4.18 and 4.18.1. The callstack shares similarities to [Link Removed], although that has been confirmed fixed in 4.18. Included in the same crashGroup are also a few Ensur ...

Distance field PrimitiveModifiedBounds grows unbounded when scene captures render with bDisableWorldRendering=true

UE - Rendering - Features - Oct 20, 2026

When UGameViewportClient::bDisableWorldRendering is true and the scene is rendered only through manually triggered scene captures, FDistanceFieldSceneData::PrimitiveModifiedBounds is never reset and ...

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:: ...