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 ...

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 ...

Visible dithered quantization to remove banding in New Temporal AA Quality

UE - Graphics Features - Oct 6, 2015

Since changing the temporal history buffer to 11:11:10 from FP16, it looks as there is visible dithered quantization to remove banding when rendering. (Taken from conversation on Forum Post linked f ...

External Reference Spam when converting projects to 4.9

UE - Foundation - Core - Cooker - Sep 1, 2015

Map Check message log gets spammed with External Reference warnings when a project is converted to 4.9 from a previous engine version. These warnings don't seem to actually do anything to projects o ...

TextRender components do not update until blueprint is saved and compiled

UE - Gameplay - Blueprint - Aug 25, 2015

TextRender components do not update when text is changed on compile. The blueprint must be saved, closed, and re-opened for the change to take effect. ...

Cannot change inherited variable default values through details panel

UE - Gameplay - Blueprint - Aug 19, 2015

Child blueprints cannot change the default values of inherited variables. ...

Pressing "+" element in landscape grass type asset crashes editor

UE - LD & Modeling - Terrain - Landscape - Jul 31, 2015

Creating a landscape grass type and then pressing the + to add an element crashes the editor. Frequency: 2/2 Crashreporter: not currently available ...