Iris - Server fails to send client initialization RPCs after seamless travel if the client finishes travelling first

UE - Networking - Iris - Nov 18, 2025

During seamless travel, when a client loads into the destination level it will call APlayerController::ServerNotifyLoadedWorld, including when it finishes the travel before the server. When the serv ...

Does FSlateElementBatcher::AddCachedElements need to check if r.HDR.UI.CompositeMode is enabled?

UE - Editor - UI Systems - Aug 28, 2024

When a specific configuration of HDR cvars are set, PIE in a New Editor Window will not render the game world. Settings (For DefaultEngine.ini): ```[SystemSettings] r.AllowHDR=1 r.HDR.Display.Color ...

Controller Mapping/Unmapping on some platforms is not ideal for local multiplayer

UE - Gameplay - Input - Nov 19, 2025

[Link Removed] The workaround is as I posted in the UDN, to override the viewport client or to make a custom slate input mapping to change this behavior. But, there is a bug with that unmapping/l ...

[AI] WP Dynamic navmesh fails to rebuild tiles with actors that are loaded but not part of the base navmesh.

UE - Runtime - Character - Feb 18, 2025

WP dynamic navmesh does not properly react to actors or navigation modifiers that are loaded in areas that the navmesh has not yet streamed into. Although the actors/modifiers are not part of the ba ...

Regarding TObjectPtr performance regression

UE - Core - Systems - Jul 13, 2026

This is from the linked EPS case: ============================== When 5.0 first introduced TObjectPtr, the guidance was that it would compile down to raw pointer access in Shipping builds to ensu ...

UNetDriver server-side hitch results in ActorInfo->NextUpdateTime far into future

UE - Networking - Feb 16, 2024

A high UWorld::Tick DeltaSeconds (i.e. GameThread hitch) results in a high UNetDriver::TickFlush DeltaSeconds. This DeltaSeconds can high (many seconds) if the hitch is long. This value then affects ...

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

UE - Runtime - Deformable - 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 ...

Unexpected corrections when sliding against other characters

UE - Gameplay - Player Movement - Oct 19, 2023

We are seeing unexpected movement corrections sometimes when pushing one player character up against another character that isn't moving, or against other static primitives that have round features ...

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

UE - Runtime - Deformable - Oct 18, 2024

Might relate to issue [Link Removed] In Progress - "The Remove-On-Break feature, set on Fracture Mode on Geometry Collectio ...

Calling BodyInstance.UpdateBodyScale displays erratic behaviors and does not update the rendering scale

UE - Runtime - Simulation - Nov 22, 2024

Calling BodyInstance.UpdateBodyScale displays erratic behaviors and does not update the rendering scale. The licensee has reported and presented a repro project that displays the erratic behavior of ...