The Remove-On-Break feature, set on Fracture Mode on Geometry Collections, stops shrinking and shows strange behaviors

UE - Simulation - Visual - Oct 15, 2024

The Remove-On-Break (ROB) feature, set on Fracture Mode on Geometry Collections (GC), was supposed to make the particle shrink until it vanishes. When the GC goes to sleep the shrinking stops and sh ...

Physics Constraint Actor: When plasticity is enabled, Drive Position Target is reset to zero on constraint initialization

UE - Simulation - Core - Mar 5, 2026

When a Chaos joint constraint is first created, having linear/angular plasticity enabled will unexpectedly force its linear/angular drive position target to zero on initialization, disregarding the ...

Paper2D: Editor hangs when assigning Sprite Atlas Group to Sprite

UE - Gameplay - Paper2D - Dec 16, 2025

In UE 5.3 and later, assigning a Sprite Atlas Group to a UPaperSprite asset can cause the editor to hang and eventually crash. This behavior has been reproduced in 5.3, 5.6, and a recent UE5-main so ...

Children of blueprints resaved by reference fixups can have invalid asset registry tags

UE - Gameplay - Blueprint - May 18, 2020

If a parent blueprint has data that is used by asset registry tags such as the AssetBundleData, any child blueprints that derive from it will use that in their exported tags. If the parent blueprint ...

Moving a mesh with complex-as-simple collision clears overlaps previously detected by moving collision components

UE - Simulation - Core - Jun 26, 2024

Consider a static mesh set to use complex-as-simple collision, and a convex collision component, starting to overlap each other. When only the Collision Component moves, its collision with the stat ...

[AI] Debug Render Scene Proxy hits ensure for registering a delegate twice during level streaming.

UE - AI - Debugging - Aug 31, 2022

Description from licensee: We're seeing an ensure get tripped up in FDebugRenderSceneProxy that says "DrawDelegate is already Registered!". Debugging the issue, we have confirmed that the DrawDeleg ...

Android compile failure with GearVR

UE - Platform - XR - Jul 11, 2017

Compiling failure from several compile errors in the output log. They're of same type like this:UATHelper: Packaging (Android (ETC2)): xgConsole: In file included from D:\Streams\UE4_Release\Engine\ ...

Gameplay Tags sourced from a Composite Data Table do not reflect changes made to its parent tables

UE - Gameplay - Gameplay Tags - Dec 5, 2025

When a Composite Data Table is included in the "Gameplay Tag Table List" on the Project Settings, making and saving changes to one of its Parent Tables does not cause the Gameplay Tag Tree to refres ...

For a TMap with C++ enum keys, deleting and re-adding a map entry in the Editor can corrupt the map data.

UE - Editor - Workflow Systems - Jul 19, 2024

When adding an entry to a TMap using UE's property editors, in most cases the new entry comes with a default-initialized key (if such key already exists, the insertion fails). The case of a UENUM de ...

Player Character does not collide with landscape

UE - LD & Modeling - Terrain - Landscape - Mar 8, 2015

UPDATE: 3/9/2015 Additional Information: User on thread https://answers.unrealengine.com/questions/186928/landscape-collison-issues-recreatelandscapecollisi.html reported workaround did not fix e ...