Crash when using StaticDuplicateObject with mismathced Source and Destination class types

UE - Foundation - Jun 19, 2025

Starting in Unreal Engine 5.4, StaticDuplicateObject internally switched to using Unversioned Property Serialization (UPS) for performance reasons. However, UPS assumes the source and destination ob ...

[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 ...

Non-Uniform Mobile Content Scale Values Render Black Screen when Launching to Mobile Device

UE - Platform - Mobile - Mar 3, 2015

When attempting to set the configuration for mobile devices within the Engine/Config/DefaultDeviceProfiles.ini, any value that is non-uniform like 1.2 or 1.6 will render a black screen after deployi ...

[CrashReport] UE4Editor_LevelEditor!FLevelEditorActionCallbacks::Paste_CanExecute() [leveleditoractions.cpp:1602]

UE - Gameplay - Blueprint - Jan 17, 2017

This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Descriptions from users are provided below. Error message: Assertion failed: GEditor->GetSele ...

Second UVs wiped when using Merge Actors Tool

UE - World Creation - Worldbuilding Tools - HLOD - Jan 26, 2017

The merge actor tool no longer saves additional UVs used for the merged mesh. This was not the case in 4.13, but in 4.14 and later this information is no longer present. Also worth noting is that i ...

ControlRig & Sequencer: FindControlRigs returns rigs even if their track have been removed

UE - Anim - Rigging - Jun 5, 2024

Constraint Actor to Rig with Editor Utility Widget is working for the first time adding to the Sequencer. However if it was deleted and added to Sequencer again, run Scripted Actor Action shows Err ...

Unreal Editor 5.4.4 crash when reproducing a LevelSequence in loop while PIE.

UE - Anim - Sequencer - Sep 9, 2024

A crash inside Unreal Engine Editor version 5.4.4 occurs when reproducing a Level Sequence while in PIE. This issue is a regression. It only crashes in version 5.4.4. It was working correctly in ver ...

Default UE splash logo appears briefly when launching an application with an alternate launch image on iOS

UE - Platform - Mobile - Sep 15, 2020

Various users have reported seeing the default UE splash logo appear briefly before their custom launch screen appears. This was reported to have been seen in 4.25, and did not occur for users in 4. ...

Client Characters that slide past the Server Character while on top of a Movable Actor can become de-synchronized from their Server counterpart

UE - Networking - Sep 9, 2015

Client Characters that slide past the Server Character while on top of a Movable Actor can become de-synchronized from their Server counterpart. Does not occur on top of Static Actors. Hard to expl ...

Depth reading features on devices without framebuffer fetch are relying on undefined behaviour.

UE - Platform - Mobile - Oct 26, 2016

For devices without framebuffer fetch we are relying on undefined behaviour for depth reading with decals, mod shadows and depth reading materials. (ES2 spec: 3.8.6 Texture Framebuffer Attachment). ...