World Memory Leaks crash with a hidden sublevel to a redirector

Tools - Dec 8, 2020

From UDN: The reason it crashes is because Child doesn't get garbage collected, which is because it still has the RF_Standalone flag. UEditorEngine::EditorDestroyWorld clears RF_Standalone flag ...

[CrashReport] UE4Editor_Slate!FDelegateBase::Unbind()

UE - Editor - UI Systems - Slate - Jul 24, 2017

This is a common crash affecting users in 4.16. User Descriptionstrying to import a texture D: Source Context 137 /** 138 * Unbinds this delegate 139 */ 140 ...

Mutable: Child parameters hidden when intermediate Object Group uses "All Options"

UE - Anim - Mutable - Mar 31, 2026

FCustomizableInstanceDetails::FillChildrenMap() unconditionally registers parent-child relationships via __ParentParamName metadata without verifying the parent exists in the active parameter list. ...

[CrashReport] UE4Editor_Engine!USkeleton::GetMeshLinkupIndex() [skeleton.cpp:420]

OLD - Anim - Jul 19, 2017

This is a common crash affecting users in 4.16, unfortunately they have not provided any additional information. Source Context 406 if ( IndexPtr == NULL ) 407 { 408 L ...

Translucent Wireframe Materials Exhibit TSR Aliasing/Crawling Due To Incorrect Velocity Rendering When Set to Output Depth And Velocity

UE - Rendering - Graphics Features - Nov 27, 2025

Note that this bug potentially also affects a wide variety of material / geometry setups; however, a translucent wireframe setup is currently the main reproduction case. The issue may also be notice ...

GameInstance and subsystem initialization order is incorrect for Play In Editor

UE - Gameplay - May 18, 2023

The order of world and game instance initialization is different between a true standalone game (cooked game or an editor build with -game) and a Play In Editor game. Specifically, in Play in Editor ...

Event Dispatcher not being called in 4.6

UE - Gameplay - Blueprint - Dec 8, 2014

ED nodes in 4.6 but are not being executed in standalone or cooked games. Also, users receive compile errors when the project is saved and reopened that resolve when the blueprint is recompiled. ...

Pre-UE5 serialized FVariant FVector data corruption when deserialized in UE5

UE - Framework - LWC - Jan 15, 2024

FVariant is a struct that implements a union of data types, including FVector. When assigning an FVariant an FVector value in engine versions UE 4.27 or earlier, the FVariant will deserialize incorr ...

Calling UBlueprintMapLibrary::GenericMap_Find with a non-existent key causes a memory leak

UE - Framework - Blueprint - Apr 15, 2025

When Calling UBlueprintMapLibrary::GenericMap_Find with a non-existent key, the function construct the default structure in-place on the given pointer without destroying the object. This behavior ca ...

[CrashReport] UE4Editor_CoreUObject!UPackage::Save() [savepackage.cpp:4597]

UE - Gameplay - Blueprint Compiler - Jul 14, 2017

This is a common crash affecting users in 4.16. Users have not provided additional information. Source Context// Set the parent index, ifthis export represents a UStruct-derived object 4589 ...