[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 ...

t.MaxFPS 0 locks FPS to 120 instead of unlocking it in Viewport

Tools - Nov 7, 2017

When unlocking FPS in Viewport it defaults to 120 instead of potential max FPS. If you do this during Launch the 't.MaxFPS 0' or 't.MaxFPS -1' commands unlock the FPS to the max the GPU allows in th ...

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

UE - Gameplay - 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 ...

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 ...

Anim curves default back to 0.f instead of material default

OLD - Anim - Sep 13, 2017

This seems to be a regression of [Link Removed]? Difficult to say. Originally reported here: https://udn.unrealengine.com/questions/391665/animcurve-parameter.html ...

Fixing a Blueprint's compilation error after editor reload causes instances to lose transform

UE - Gameplay - Blueprint - Feb 23, 2023

Saving and reloading a Blueprint instance with a compilation error, a.k.a., "Bad Blueprint" will lead to a transform reset when the Blueprint is successfully recompiled. ...