Editor crashes if opening a sublevel containing a navmesh when persistent level is open

UE - AI - Sep 8, 2015

If the persistent level is open and a user attempts to open a sublevel that contains a navmesh, the editor will freeze and then crash. Frequency: 3/3 Crashreporter: N/A ...

Android ETC2 Debug Builds Crash on Startup

UE - Platform - Mobile - Sep 9, 2020

Android apps build with the debug configuration on ETC2 will crash on launch. ...

Crash when using Ctrl+Z to undo a single digit change in the size of a widget

UE - Anim - Sequencer - Feb 21, 2017

When trying to undo a single digit change the editor will crash. For example, if a user highlights and replaces a single number in the size of a widget and then attempts to undo, the editor will cra ...

Lighting channels not working as expected when enabling Ray Tracing Shadow

UE - Graphics Features - Lumen - Oct 13, 2020

Non-Ray Tracing Shadows are only cast from lights on meshes assigned to the same Lighting Channel. When enabling Ray Tracing Shadows this is not the case. Lights will still cast Ray Tracing Shadows ...

Mobile Preview -> AutoLandscape Material broken if created in 4.22+

UE - Platform - Mobile - Oct 25, 2019

Landscape Layers created in 4.22+ revert to default material in Mobile Preview. Confirmed in MAIN at CL 9730599 ...

Launching the editor with -d3ddebug and enabling LOD Coloration mode gives D3D11 DEVICE_PSSETSHADERRESOURCES_HAZARD warning

UE - Graphics Features - Nov 3, 2015

Launching the editor with the "-d3ddebug" command line option and then enabling the "LOD Coloration" view mode (under "Lit") results in the following D3D warning: D3D11 WARNING: ID3D11DeviceContext ...

Crash, Couldn t find Shader FHitProxyVS for Material Resource M_Glass

UE - Graphics Features - Aug 18, 2014

Changing the properties of M_Glass and M_Metal_Copper to two sided via the property matrix crashes the editor to desktop. (Note: M_Glass with ANY of the M_Metal Materials except M_Metal_Chrome will ...

Crash when using StaticDuplicateObject with mismathced Source and Destination class types

UE - Foundation - Jun 19, 2025

Starting in Unreal Engine 5.4, StaticDuplicateObject internally switched to using Unversioned Property Serialization (UPS) for performance reasons. However, UPS assumes the source and destination ob ...

Editor crash when adding mesh renderer elements in Niagara

UE - Niagara - Jul 8, 2025

When adding multiple meshes to a Niagara Mesh Renderer Module, a check() will be triggered due to a mismatch in the number of Widgets and the number of Tooltip Widgets. ...

GAS: Removing an AttributeSet followed by removing an active GameplayEffect results in client crash

UE - Gameplay - Gameplay Ability System - Aug 23, 2023

Gameplay Ability System Standalone: Removing an attribute set and then removing an active gameplay effect that has a modifier for an attribute from that set results in a crash. Currently, one must ...