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 ...

Animation Modifiers that contain a null Animation Sequence value cause the Engine to crash when applied to an Animation Sequence

OLD - Anim - Nov 14, 2018

When an Animation Modifier passes a null Animation Sequence value to an Animation Sequence the Editor will crash. This is a regression from 4.20.3 (CL-4369336). This was reported and tested in 4.21 ...

UMG widgets with instanced properties reset those properties to default on compilation

UE - Editor - UI Systems - Feb 2, 2016

This is perhaps a misuse of Instanced properties but the repro info is good so I thought I'd better add it to Jira. See Additional Info URL for details. Checked and happening on: //UE4/Main CL-2884 ...

Editor primitives render incorrectly in stereoscopic with instanced stereo

UE - Platform - XR - Aug 17, 2016

Trigger box icons move around when oculus head movement is used. Found in //UE4/Release-Staging-4.13 @ 3090357 QA-Promotion map Edit: 08-22: This affects volumes as well as their editor icons, upd ...

ShowDebug Overlapping Text

Tools - Apr 27, 2016

Using the showdebug commands during play results in overlapping text that is difficult to read. Found in 4.11.2 binary. Reproduced in 4.10.4 binary and Main CL 2852833. Regression? No, also occ ...

Using Blend Physics Weight causes skeletal mesh to spin at high speed

OLD - Anim - Mar 5, 2015

When Phyics Blend in the PHAT editor is set between 0 and 1, the user character will spin wildly. User has image of this affecting character in game whereas I was only able to replicate it in the PH ...

Using FEditorModeID for the "Mode" console command does not switch the modes tab

Tools - May 10, 2016

Using the FEditorModeID for the different editor modes does not affect actual modes available in editor Modes tab. Example: Command "Mode EM_Foliage" does not switch to the foliage mode Workaround ...

Child Actor component is duplicated in Standalone Game

UE - Gameplay - Jan 12, 2017

Child Actor component is duplicated in Standalone Game. No other play modes or packaged game are affected. The additional actor will disappear after 1 minute. *This is a regression: Doesn't occur ...

Set All Bodies Below Simulate Physics Only Causes Ragdoll Effect if it is Set to Root Bone

UE - Simulation - Physics - Sep 29, 2017

-This functions in 4.16 -Physics will only simulate if the Third Person Character bone name variable is set to root -Physics does not affect any other bone -Make sure to plug in set in collision f ...