[AI] Crash when gathering heightfield geometry on worker thread

UE - Runtime - Character - Jun 25, 2025

From the body of the ticket: We aim to do as much of the work off the game thread as possible to avoid impacting frame rate. We've recently found a crash during collection of the geometry slices fr ...

Crash When Substance Material Is Applied to a Mesh In HLOD System

UE - World Creation - Worldbuilding Tools - HLOD - Sep 3, 2018

Crash when Substance material is applied to a mesh included in the HLOD system. Working as expected in 4.19 CL# 4033788. Unable to test issue in 4.21 CL# 4339215 due to plugin dependency. Found in ...

FTabManager::FindPotentiallyClosedTab Crash Due to Invalid Array Indexing

UE - VEI - May 25, 2023

As you can see from the above callstack it appears that calling RestoreArea can call FindPotentiallyClosedTab again higher in the stack, which can Remove() an entry from CollapsedDockAreas- this cau ...

Inserting before a FSlateImageRun twice will cause crash

UE - Editor - UI Systems - Apr 12, 2019

Editor crashes when attempting to play a recorded demo - Assertion failed: IsGameWorld() && GetCurrentLevel()

UE - Networking - Oct 9, 2018

Editor crashes when attempting to play a recorded demo - Assertion failed: IsGameWorld() && GetCurrentLevel() This issue occurs when using a template project or QAGame. This does not occur when usi ...

Switcher widget causes a crash when dragging a widget out of it and on to the canvas panel

UE - Editor - UI Systems - Aug 6, 2015

If the user adds two widgets to a switcher and then tries to drag one out of it the editor will crash ...

Ensures in ChaosExamples_fracture map in ChaosDestructionDemo

UE - Simulation - Physics - Destruction - Jun 4, 2019

Ensures trigger when playing in the ChaosExamples_fracture map in the ChaosDestructionDemo project. The ensures seem to happen during different parts. A couple occurrences were when I triggered th ...

Lyra: When a bot fails to fire their weapon, all bots play their weapon fire fail animation montage

UE - Gameplay - Jun 12, 2024

UDN reported: Lyra bots will sometimes play their weapon fire failure anim montage "randomly". The reporting licensee found that this happens when another bot in the level is reloading. The gamepla ...

Crash when calling SetVector2DParameter on a Niagara Parameter Collection

UE - Rendering - Architecture - Niagara - Mar 10, 2022

Crash when calling SetVector2DParameter on a Niagara Parameter Collection. The value for the SetVector2DParameter may or may not have to be changed in order for the crash to occur.  Assertion faile ...

Crash when Deleting Variable from Blueprint Struct

UE - Gameplay - May 23, 2019

The Editor will crash when attempting to delete a variable from a Blueprint struct. This crash does not seem to happen if save the map with the actor in it. ...