Level Actors that are converted to a Blueprint using "Convert Selection to Blueprint Class" and using "Harvest Components" as the CreatingMethod, does not sanitize dots (.) character and make them invalid for operations like StaticFindObject.

UE - Framework - Blueprint Editor - Feb 20, 2025

When Level Actors are converted into a Blueprint using the "Convert Selection to Blueprint Class" option with "Harvest Components" as the creation method, the conversion process does not sanitize do ...

Popping Ribbon UVs

UE - Niagara - Mar 10, 2025

Please see the Additional Link for related UDN information. The UV popping described can be subtle, depending on settings; it's affected by spawn rate and GPU vs CPU. The popping shown in the gif t ...

Enabling Override Instance Data to a LevelSequencerActor that has a Shot Track can lead to crashing the engine

UE - Anim - Sequencer - Mar 17, 2025

Enabling Override Instance Data to a LevelSequencerActor that has a Shot Track can lead to an Actor being translated really far, or even a crash in the engine. The licensee has encountered a particu ...

Niagara color picker user parameter preview no longer updates until confirmation

UE - Niagara - Apr 18, 2025

Starting with UE 5.4, the Color Picker Tool no longer updates preview values in real time for certain editor windows like Niagara when working with User Parameters. This behavior is a regression fr ...

GPU Lightmass no longer works with cascaded shadow maps

UE - Graphics Features - May 29, 2025

Since Unreal Engine 5.5 stationary lights have stopped working with GPU Lightmass when using Cascaded Shadow Maps. With Virtual Shadow Maps enabled on the project, GPU Lightmass works. This issue d ...

Light Mixer - All of the Light Attributes disappear when you have Show Only Selected enabled

UE - Virtual Production - Tools - Jun 13, 2025

All of the Light Attributes disappear when you have Show Only Selected enabled. ...

Crash in FUniformExpressionSet::FillUniformBuffer trying access deleted UTextureCollection

UE - Rendering Architecture - May 30, 2025

Crash in FUniformExpressionSet::FillUniformBuffer trying access deleted UTextureCollection (Experimental in 5.6). The licensee describes their crash, their analysis, and a proposed fix: This crash ...

Runing PlayInEditor with NetMode PlayAsClient and a LevelSequence that AutoPlays in the level and is also opened in Sequencer leads to a Fatal world leak crash on 5.5 and up

UE - Anim - Sequencer - May 28, 2025

Runing PlayInEditor with NetMode PlayAsClient, a LevelSequence that AutoPlays in the level, contains a Spawnable BP_ThirdPersonCharacter with an animation, and is also opened in Sequencer, leads to ...

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 ...

Saving Behavior Tree with Blueprint task inheriting from native class invalidates Blackboard key when BP contains a function

UE - AI - Jul 8, 2025

A regression introduced in UE 5.6 causes Blackboard key selectors in Blueprint tasks to become invalid when the Blueprint inherits from a native subclass of UBTTask_MoveTo (or UBTTask_BlackboardBase ...