Niagara Regression - Looping particle with Spawn Burst Instantaneous on time 0.0 flickers for a frame between loops

UE - Niagara - Jul 16, 2025

Note: This worked correctly up to UE 5.4, but repros from UE 5.5 up to mainline latest. If a Niagara Emitter is set up with "Spawn Burst Instantaneous" on time 0.0, and the spawned particle(s) have ...

[AI] Crash when gathering heightfield geometry on worker thread

UE - AI - Navigation - 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 ...

A GeometryCollection that was broken and is going through shrinking will reset the size of its particles if a second level is broken

UE - Simulation - Physics - Destruction - Oct 18, 2024

Might relate to issue [Link Removed] - "The Remove-On-Break feature, set on Fracture Mode on Geometry Collections, stops shrinking and shows strange behaviors" The added information on this particu ...

Crash when undoing emitter deletion in Niagara System

UE - Niagara - Cinematics - May 25, 2024

Asset localization does not work properly for Paper2D related assets such as Flipbook

UE - Foundation - Mar 18, 2022

This issue is resolved by changing Paper2D's LoadingPhase to PostConfigInit, but this is a workaround. We suggest a better long term fix via AssetRegistry changes (see comments). In the default la ...

Unreal Editor can get in an infinite while loop when checking the History of an asset under Perforce.

UE - Editor - Workflow Systems - Oct 21, 2024

Unreal Editor can get in an infinite while loop when the action Asset->Source Control->History is used in a Blueprint Asset. Reportedly, this issue is only encountered when using the Branches featur ...

Level asset "Diff against depot" opens P4 Merge tool

UE - World Creation - Worldbuilding Tools - Mar 1, 2024

You can right click a level asset in the editor's Content Browser and do the action Source Control > Diff against Depot. However, this does not provide a useful diff window. It currently opens the d ...

Crash when entering Brush Editing mode with a Sequence spawnable Post process volume

UE - Graphics Tools - Modeling Tools - BSP - Mar 18, 2024