Crash When Setting a Bool in a Niagara Parameter Collection via Blueprint

UE - Niagara - Feb 26, 2019

The Editor will crash when setting a bool in a Niagara Parameter Collection via Blueprint. Found in 4.20 CL# 4369336, 4.21 CL# 4753647, 4.22 CL# 5159901, 4.23 CL# 5194133 ...

Changing the Curve Asset in a Material Instance That Uses a Material Layer Crashes the Editor

UE - Graphics Features - Apr 22, 2019

Changing the Curve Asset in a Material Instance That Uses a Material Layer Crashes the Editor. Found in 4.20 CL# 4369336, 4.21 CL# 4753647, 4.22 CL# 5660361, 4.23 CL# 5974510 ...

"Activation" and "Trigger" keywords are not allowed as a subcategory

Tools - Jul 1, 2019

Using Activation and Trigger as subcategories names does not work in the Details Panel. Tested in 4.21.2 (CL - 4753647), 4.22.3 (CL - 7053647), 4.23 (CL - 7208101), 4.24 (CL - 7216880) ...

DisplayThumbnail doesn't work with TArray

Tools - Jul 8, 2019

The DisplayThumbnail metadata UProperty specifier does not work on TArrays with the type of FSoftObjectPath. Tested in 4.21.2 (CL - 4753647), 4.22.3 (CL - 7053647), 4.23 (CL - 7224811), 4.24 (CL - ...

Rearranging Slate Brushes causes crash

UE - Editor - UI Systems - Jul 14, 2019

Rearranging the order of a Slate Brush array causes the editor to crash. Tested in 4.21.2 (CL - 4753647), 4.22.3 (CL - 7053647), 4.23 (CL - 7305105), 4.24 (CL - 7285696) ...

Adding a camera cut track through sequencer scripting does not set the movie scene's camera cut track

UE - Anim - Sequencer - Mar 13, 2020

When adding a camera cut track through sequencer scripting there is no way to set the camera cut track on the movie scene, which is how the add track menu determines if a new one can be added. This ...

BlackboardComponent observer can be called for the wrong key

UE - AI - BehaviorTree - Feb 7, 2023

We need to, at least, prevent this by clearing observers when running a new BT using a different blackboard. Must also think that this might affect licensees relying on the current behavior (might h ...

TranslucentVolumeAmbient is darkened in InjectTranslucencyLightingVolume pass when using VSMs with r.Shadow.Virtual.ForceOnlyVirtualShadowMaps is Off

UE - Graphics Features - Shadows - Nov 18, 2024

CSM targets are still created and affect the InjectTranslucencyLightingVolume pass when moving in a project that only uses VSM causing over brightening of fog planes and other translucent meshes. r ...

Compiling any material in UE 5.5.1 without ShaderCompiler JobCache results in a crash

UE - Rendering Architecture - Shaders - Jan 15, 2025

Compiling any material with r.ShaderCompiler.JobCache=0 causes ShaderCompileWorker to crash. Reproduction steps cause a crash during Editor startup, but this bug may affect other scenarios where mat ...

Popping Ribbon UVs

UE - Niagara - Mar 10, 2025

Please see the Additional Link for related UDN information. The UV popping described can be subtle, depending on settings; it's affected by spawn rate and GPU vs CPU. The popping shown in the gif t ...