Editor Crashes when placing a widget blueprint from one widget blueprint into another via the user created section

UE - Editor - UI Systems - Oct 8, 2014

CHANGELIST: 4.5.0-2316912 CRASHREPORT: Did not produce an error report CALLSTACK: Did not produce an error report DESCRIPTION:   Editor Crashes when placing a widget blueprint from one widget b ...

BP: DEBUG: Debug filter automatically switches to one of the instances of blueprint which doesn t let user debug other instances of blueprint

UE - Gameplay - Blueprint - Aug 5, 2014

GameVersion Branch: UE4 Configuration: Main Version: 2242091 CommandLine:qagame -log Label: GUBP Node Shared_LabelPromotable built from changelist 2242091 DESCRIPTION: Debug filter automatically sw ...

Editor ensure in USceneComponent::OnComponentDestroyed during Blueprint compilation GC

UE - Framework - Components - Jan 15, 2026

An editor-only ensure can trigger during BP compilation when garbage collection cleans up transient components created as part of component replacement. During recompilation, old component instances ...

Children of editor-only actors do not maintain correct transforms when placed inside level instances for PIE and cooked builds

UE - World Creation - Worldbuilding Tools - Level Instances - Oct 20, 2025

We have found an issue where children of editor-only actors get wrong transforms in PIE and cooked builds when placed inside level instances. This affects both engine version 5.5 and 5.6. The issue ...

[CrashReport] UE4Editor_Kismet!SBlueprintEditorSelectedDebugObjectWidget::GenerateDebugObjectNames() [sblueprinteditorselecteddebugobjectwidget.cpp:454]

UE - Gameplay - Blueprint - Dec 9, 2016

This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Error message: Access violation - code c0000005 (first/second chance not available) Source C ...

[CrashReport] UE4Editor_Engine!UAnimMontage::IsValidAdditive() [animmontage.cpp:702]

OLD - Anim - May 19, 2016

Error message: Stack overflow - code c00000fd (first/second chance not available) Source Context: 687 if (SyncGroup != NAME_None) 688 { 689 CollectMarkers(); 690 ...

Incorrect Velocity Calculation at Animation Sequence Transitions in Level Sequence

UE - Anim - Sequencer - Feb 18, 2025

When adding an Animation Track to a Level Sequence and placing Animation Sequences back-to-back without gaps, the velocity can be miscalculated at the transition between sequences. This issue occur ...

Undo after disconnecting a target pin will cause a series of internal compile errors

UE - Gameplay - Blueprint - Mar 15, 2016

Undo after disconnecting a target pin will cause a series of internal compile errors User Description: I've run into what I think is a bug when attempting to compile a blueprint after mistakenly b ...

[AI] Bad entries in NavigationRepository for Box collision with bCanEverAffectNavigation set to false

UE - AI - Navigation - Oct 26, 2025

Some components continue to dirty the navigation state even if bCanEverAffectNavigation is unchecked. Behavior appears very similar to an existing bug, [Link Removed] ([Link Removed]), which invol ...

Crash rendering image sequence if the Sub-Level with matinee is not loaded

Tools - Apr 15, 2016

Crash rendering image sequence if the Sub-Level containing the matinee is not loaded. This seems to go away if the level is either set to "Always Loaded". Seems to be a result of people not switch ...