Importing a New Substance Preset will crash the engine

UE - Foundation - Core - May 13, 2015

With the Substance plugin installed and when you try to import new preset data into the Substance Graph Instance, the engine will crash ...

FLiveCodingModule::StartLiveCoding() unsafe access of FModuleManager::Get().OnModulesChanged()

UE - Foundation - Cpp Tools - Live Coding - Dec 19, 2023

A user has reported a failing ensure in FMRSWRecursiveAccessDetector::AcquireWriteAccess(), a race condition that has a small chance of happening when launching the editor. FLiveCodingModule::Start ...

Opening widget blueprint causes editor to crash

UE - Editor - UI Systems - Oct 17, 2014

Branch Build Label UE4-Main Promoted-CL- 2323471 DESCRIPTION: User crashes when opening a Widget blueprint.  Unable to reproduce internally. *EDIT* Repro provided by User ...

USD Stage - Assert !EdgeArray[EdgeID].ConnectedPolygons.Contains(PolygonID)

UE - Editor - Content Pipeline - Import and Export - Nov 19, 2019

One of Pixars example .usd files is crashing the editor when importing with 'USD Stage' (KitchenSet imports with no errors) It is possible to import the file via content browser without crashing. ( ...

Lyra 5.5 - LAS_ShooterGame_SharedInput has got a missing reference on InputMapping #1

UE - Gameplay - Input - Jan 27, 2025

The templated Lyra project for 5.5 is missing a reference to IMC_Default_KBM on /ShooterCore/Experiences/LAS_ShooterGame_SharedInput because it looks like IMC_Default_KBM was renamed to IMC_Default. ...

Crash when splitting up output of collapsed node

UE - Gameplay - Blueprint Compiler - Feb 13, 2017

A crash occurs when splitting the pin of a collapsed vector node that was connected via a vector connection. This issue is very similar to [Link Removed] however, the callstacks are different so I ...

Packaged ThirdPerson template with "start in vr" enabled packaged and launched with "-nohmd" crashes

UE - Platform - XR - Mar 31, 2021

The callstack is not XR-specific, it's just the engine trying to secure the audio device on startup, windows failing to return one, and the app not being able to continue safely. The crash does not ...

The CTRL+S shortcut does not save an opened Sequence it the Sequencer Window is undocked

UE - Anim - Sequencer - Jul 29, 2025

The CTRL+S shortcut does not save an opened Sequence it the Sequencer Window is undocked. Docking the Sequencer Window to the main window fixes the issue. I've reproduced the behavior on UE versions ...

Crash when updating phsyics simulated box extent during runtime

UE - Simulation - Physics - May 12, 2017

If a Box Collision component is set to simulate physics, calling "Set Box Extent" causes the editor to crash. Workaround: Setting Collision Enabled for the box component to "Physics Only" or "Query ...