PCG crash when using Attribute Remove Duplicates on partitioned data if one of those sets of data is empty

UE - World Creation - Procedural Tools - PCG Graph - Jul 3, 2025

Context: In PCG, the Attribute Remove Duplicates node can be used to remove duplicate attributes from an array. Problem: The licensee has observed that using the Attribute Remove Duplicates node ...

BP using nested child actor components in streaming level causes ensure condition failed

UE - Simulation - Core - Jul 11, 2022

This never happens on ue5.0.0 The problem appears to be caused by a deleted PhysicsProxy being registered with Solver. Since the solver accesses the deleted PhysicsProxy, it may crash. Checking a ...

Can perform infinite "double jumps" when JumpMaxHoldTime is greater than 0.

UE - Gameplay - Player Movement - Jun 3, 2016

There's a bit of broken (or missing) logic in ACharacter that doesn't account for users having released the jump button. This is a well known issue, and there's even video's describing how users can ...

[CrashReport] Assertion failed: OLEReferenceCount == 0 in UE4Editor_SlateRHIRenderer!FSlateRHIRenderer::DrawWindows_Private()

UE - Editor - UI Systems - Slate - Aug 22, 2017

This is a regular and longstanding crash in 4.17 that has occurred since at least 4.14. Users have not provided any descriptions of their actions when the crash occurred. There has been some previo ...

ensure(PinHelpers::UnresolvedPins.Num() == 0); fails after undoing in the editor

UE - Framework - Blueprint Editor - Sep 6, 2025

The underlying cause is some edge case involving a math expression node, which does some perhaps naive things with a contained graph. ...

Skeletal mesh LOD 0 "LOD Info" loose their settings when we reimport

UE - Editor - Content Pipeline - Import and Export - Mar 6, 2020

Set critical because loosing settings is dangerous. This is not a regression, the bug is in 4.22 and earlier version. We have to save all options of the LODInfo, currently nothing is saved. Also sh ...

Getting Emitter.NumParticles on Niagara's GPU compute sim returns 0

UE - Niagara - Jul 27, 2023

This problem looks like the following parameters are not defined correctly. The correct parameter is Engine_Emitter_NumParticles. Engine_Emitter_NumParticles and PREV_Engine_Emitter_NumParticles .\ ...

[CrashReport] UE4Editor_PropertyEditor!FPropertyEditor::IsEditConditionMet() [propertyeditor.cpp:632]

Tools - Oct 27, 2017

This is a trending crash coming out of 4.18.0. The issue appears similar to [Link Removed], which was just fixed in 4.18. User DescriptionsProject was just imported from UE 4.17.2 , opened a bluep ...

[MRQ] Deleting all jobs after rendering queue with executor causes an assertion to fail.

UE - Anim - Sequencer - MRQ - Apr 18, 2022

Deleting all jobs after rendering queue with executor causes an assertion to fail. Repro Rate: 3/3 Tested this in //UE4/Release-4.27 @ CL#18319896 by utilizing a For Each Loop and Delete Job node ...