Lighting behavior is unreliable for translucent lit materials, results are inconsistent depending on the editor camera's FOV and the editor viewport's width/height/aspect

UE - Rendering Architecture - Oct 27, 2024

When working on the level editor viewport or testing on PIE, the visual appearance of additive/translucent lit materials changes significantly (and abruptly) when varying the camera FOV or the viewp ...

FIndexedCurve::ScaleCurve returns invalid results

UE - Anim - Runtime - Feb 13, 2025

Calling SetKeyTime in iterating KeyHandlesToIndices array can modify the array order, so it breaks the iterator. Perhaps ShiftCurve also has the same problem. Here is a work around: void FIndexedCu ...

Result pin of Cast Node of ControlRig can not break

UE - Anim - Rigging - Control Rig - Jul 26, 2023

In UE5.1, the Result pin of the ControlRig cast node could be broken, but it cannot be broken from UE5.2. ...

Simulate motion vectors can fail on camera cuts

UE - Anim - Sequencer - Jun 11, 2024

r.MotionVectorSimulation 1 should simulate motion vectors when cutting cameras, but this appears to be broken on some loops. ...

The visibility state of on-screen stat messages is not restored correctly after entering and leaving PIE. This also affects other important on-screen messages like map warnings and debug messages.

UE - Editor - UI Systems - Nov 28, 2024

Currently, the ShowStats viewport option is automatically enabled when entering PIE and automatically disabled when exiting PIE. This forced disabling happens even if the option was enabled prior to ...

Jump Animation for FPS template character breaks on land

OLD - Anim - May 6, 2015

When jumping in the first person template project, the "is in air" animation continues to play after landing. Solution: Switching out the "FirstPerson_JumpStart Asset" node for the "FirstPerson_J ...

For each "EnumName" nodes do not update when passed into a create widget node via an exposed variable

UE - Gameplay - Blueprint - Nov 1, 2016

For each "EnumName" nodes do not update when passed into a create widget node via an exposed variable ...

UE5.6+ - Mutable - IDPrefix crash when combining Child Objects, Add to Mesh Component and Extend Mesh Section.

UE - Anim - Mutable - Jul 21, 2025

So the issue seems to be a combination of Add To Mesh Component and Extend Mesh Section. I've tried this in Epic Launcher 5.6, 5.6 in-house modified engine as well as ue5-main 5.7 from git (editor ...

Enable Slate layout caching Will cause the Stop/Play Buttons to disappear

UE - Editor - UI Systems - Slate - Dec 17, 2018

When using the command Slate.EnableLayoutCaching 1, The Play button is removed from the tool bar after exiting play. ...

InstancedStaticMeshes disappear in Shipping builds on mobile when affected by dynamic point lights

UE - Platform - Mobile - Aug 22, 2019

This ticket is to add the safe workaround for 4.23.1, with a more optimal fix coming in 4.24. ...