Niagara color picker user parameter preview no longer updates until confirmation

UE - Niagara - Apr 18, 2025

Starting with UE 5.4, the Color Picker Tool no longer updates preview values in real time for certain editor windows like Niagara when working with User Parameters. This behavior is a regression fr ...

Crash on iOS9 when using Apple's CFNetwork library

UE - Platform - Mobile - Dec 6, 2016

Many clients have hit a crash due to an Apple library using operator delete on a memory block that was not allocated with operator new. This happens with the following callstack on iOS9 in UE4.13 o ...

Behavior Tree (BT) services added to root nodes call the initial tick twice

UE - AI - Nov 20, 2024

Behavior Tree (BT) services added to root nodes call the initial tick twice A BT Service with the setting "Call Tick on Search Start" enabled will execute the initial tick twice when added to the ro ...

BuildPatchTool crashes on Mac and Linux when building android or ios with multiple chunks

Portal - Feb 18, 2020

"It seems that deallocation of TLazySingleton<FInternationalization> causes unhandled exception. If DISABLE_LAZY_SINGLETON_DESTRUCTION=1 is provided - the build completes successfully" ...

[CrashReport] Linux crash - FVulkanDynamicRHI::Init()

UE - Platform - Linux - Aug 16, 2017

This is a trending Linux crash in 4.17.0 that has also occurred in 4.16 Callstack from LogLogLinux: Error: appError called: Assertion failed: Assertion failed: [File:/home/---/UnrealEngine/Engine/ ...

Crash can occur when calling GetSkinnedVertexPosition on a skeletal mesh with a slightly different bone hierarchy than the skeletal mesh whose skeleton it is using

OLD - Anim - Apr 12, 2017

MDW: In progress (Dev-AnimPhys CL 3392820) When calling GetSkinnedVertexPosition on a skeletal mesh that uses the same skeleton as a different skeletal mesh with a slightly different bone hierarchy ...

Search field in 'Quickly Add to Project' fails with Chinese Pinyin input unless manually focused

UE - Editor - UI Systems - Localization - May 28, 2025

A licensee reported that under the Chinese language setting in UE5, using the “Quickly Add to Project” button results in incorrect or ignored input when entering text via Pinyin IME. If the user sta ...

Fracture Mode > "Remove-On-Break" setting: Cluster Crumbling causes flickering

UE - Simulation - Visual - May 10, 2025

Fracture Mode > "Remove-On-Break" setting: Cluster Crumbling causes flickering. Once the Remove-On-Break Cluster Crumbling effect is activated, there is a small delay between the disappearance of th ...

[CrashReport] UE4Editor_UnrealEd!UEditorEngine::CheckForWorldGCLeaks()

UE - Foundation - Core - UObject - Jun 29, 2017

This is a common crash occurring for users in 4.16. It is spread out among around 60 different CrashGroups in CrashReporter, because every case has a slightly different callstack. This appears to ...