Iris - Ensure hit when destroying a torn off actor from AActor::TornOff

UE - Networking - Iris - Dec 11, 2025

As of CL 42014318, StopReplication requests that occur during ReceiveUpdate are delayed until all received data from the update is finished processing, including if the actor is torn off. However, i ...

Replicated timeline may not call Finished event on client

UE - Networking - Dec 9, 2025

It seems this can happen if the timeline component on the client receives an update from the server for the final position of the timeline, causing it to be set as no longer playing before it has a ...

Texture Streaming can randomly streams in all Mips, causing large memory spikes

UE - Graphics Features - Dec 5, 2025

A possible race condition allows texture instance views to read uninitialized bounds, causing either garbage or zero screen size values to be returned by FRenderAssetInstanceAsyncView::GetRenderAsse ...

Drag and Drop fails in Standalone and Packaged builds when WidgetComponent’s Widget is set at runtime

UE - Editor - UI Systems - Dec 4, 2025

When a UWidgetComponent has its widget assigned dynamically at runtime using CreateWidget and SetWidget, drag & drop operations fail in Standalone Game and packaged/game builds, while working correc ...

Mover plugin: Crash on UFloorQueryUtils::ComputeFloorDist() and other utility functions that assume the pawn uses a UCapsuleComponent

UE - Gameplay - Player Movement - Mover - Dec 4, 2025

The following functions have been found to perform unchecked casts of the pawn's "UpdatedComponent" to class UCapsuleComponent, possibly resulting in crashes:UFloorQueryUtils::ComputeFloorDist()UGro ...

Unreal Engine Fails to Launch with Vulkan SM6 RHI and RenderDoc Auto-Attach Enabled

UE - Rendering Architecture - RHI - Dec 3, 2025

When launching Unreal Engine with the Vulkan RHI, SM6 and RenderDoc Auto Attach on Startup enabled, the engine fails to initialize with the error: “A compatible Vulkan Driver is required to run the ...

PIE also rendering in-active / unfocused editor viewport

UE - Graphics Features - Nov 28, 2025

In 5.8, after entering PIE, the editor will start doing two SceneRenders per frame. This dramatically drops performance. Presumably this second render is for the inactive / unfocused editor viewport ...

SaveGeneratedTexture2DAsset can crash when overwriting an existing asset

UE - Texture - Nov 28, 2025

SaveGeneratedTexture2DAsset can crash for a variety of reasons when overwriting an existing texture asset. When no existing asset exists, the function simply moves the provided transient Texture ass ...

Morph target normals not correctly applied when imported as LOD 0

UE - Editor - Content Pipeline - FBX - Nov 27, 2025

This is a regression since 5.5 with skeletal meshes where morph target normal/tangent deformation only works when a mesh is imported as a LOD of an existing skeletal mesh, but not when imported as L ...

Translucent Wireframe Materials Exhibit TSR Aliasing/Crawling Due To Incorrect Velocity Rendering When Set to Output Depth And Velocity

UE - Graphics Features - Nov 27, 2025

Note that this bug potentially also affects a wide variety of material / geometry setups; however, a translucent wireframe setup is currently the main reproduction case. The issue may also be notice ...