Navigation obstacles remain when turning off bCanEverAffectNavigation in Blueprint actor

UE - AI - Nov 30, 2018

Editing the bCanEverAffectNavigation flag on an Actor Blueprint is propagating the value of the property to the Blueprint instance, but fails to properly update the navmesh according to the new valu ...

Navigation Mesh ignores Hierarchical Instanced Static Meshes using "Build Paths" or the "Build" Button

UE - AI - Feb 1, 2019

Hierarchical Instanced Static Meshes are partially ignored after building the navigation mesh. This is causing the navmesh to be generated within all or part the HISM instead of around it.  This ...

Codeworks fails to install under Ubuntu 18.04 and later

UE - Platform - Linux - Apr 28, 2020

Codeworks is packaged with Unreal engine download from Github, but depends on Libpng12, which is deprecated. Current version of Libpng is Libpng16 ...

Ray traced shadow sample settings greater than 1 cause shadow artifacts

UE - Graphics Features - Lumen - Sep 23, 2020

Alternative you can follow these steps to reproduce 1. Create a new project with ray tracing enabled 2. Activate the groom plugins 3. Import a groom asset into the scene 4. Add any light type to the ...

Enabling Window Animations causes drop down menus to flicker and be displaced

UE - Editor - UI Systems - Slate - Mar 10, 2021

I tested this with 3 Nvidia Drivers to see if I could find a driver that works properly. I tested the following Game Ready drivers Version 457.30, 461.40 and the latest, 461.72. The flicker occurred ...

"PivotPainter_PerObjectData" node's "Random Value Per Element" output crashes with an assertion when used with a "Cross" node

UE - Rendering Architecture - Materials - Jan 31, 2022

This is a regression. Tested in: //UE4/Release-4.27 CL18319896 Binary //UE5/Release-5.0 CL18747223 GitHub When using the Random Value Per Element from a PivotPainter_PerObjectData with a Cross nod ...

Nanite displacement on landscapes not rendering on 5700XT

UE - Graphics Features - Nanite - Mar 27, 2024

This only happens on a 5700XT, tested this on the 7900XT and the issue did not occur  Initially reported on the Preview 1 forums: https://forums.unrealengine.com/t/unreal-engine-5-4-preview/1763516 ...

3D Grass may not appear in Path Tracer renders

TM - Rendering - Sep 19, 2025

Reported in SF [Link Removed] Path Tracer renders of images with 3D grass may not display 3D grass in the foreground of an image. The 3D grass material will not appear or may appear to cut off at s ...

Widget "Listen For Input Action" executes on unexpected input event

UE - Editor - UI Systems - Feb 19, 2020

Listen For Input Action firing erroneously. Confirmed in 4.26 MAIN @ CL 11536993 ...

Particle disappears if it is using PSA_Velocity and setting custom time dilation 0

UE - Graphics Features - Dec 7, 2016

A licensee reported some of their particles disappear when setting the actor's custom time dilation 0. This seems to happen when a particle is using PSA_Velocity as Screen Alignment. This repros in ...