Crash undoing variable change in Animation Blueprint.

OLD - Anim - Aug 1, 2016

Crash occurs when the user changes a variable in the animation blueprint, and then undo's the change. Note that this occurs with any variable being used, but the callstack will be some what differe ...

File handles remain open on Shipping Windows build after assets have finished loading

UE - Foundation - Core - Oct 14, 2015

This developer has a game that they are targeting a Windows-based arcade machine for, but they noticed that while the game is running there are several hundreds or thousands of file handles left ope ...

tvOS encounters failure to read save file when loading saved level

UE - Platform - Mobile - Nov 20, 2019

When load is called user encounters: [UE4] [2019.11.20-23.42.09:282][575]LogStreaming: Warning: Failed to read file '../../../QAGame/Saved/SaveGames/TestSlot.sav' error. The integer value does not ...

Linked animation graph doesn't trigger anim notifications on dedicated server.

OLD - Anim - Jun 15, 2020

Linked animation graph doesn't trigger anim notifications on dedicated server. There is no expected message in log: LogBlueprintUserMessages: [HitReact_AnimBP_C_0] Client 0: HitNotify IsServer: tru ...

Reimporting sprite sheets does not work correctly if the editor has ever been closed and reopened since initial import

UE - Gameplay - Paper2D - Aug 1, 2020

UPaperSprite::PostLoad() now sets BakedSourceTexture, BakedSourceUV, and BakedSourceDimension (if AtlasGroup is nullptr). There's nothing in reimport that sets them, so they are stale/latch to the ...

FDeferredDecalProxy cannot be initialized to not fade even if FadeDuration is set to 0

UE - Rendering - Architecture - May 16, 2024

FDeferredDecalProxy always fade because InitializeFadingParameters is always called and leaves InvFadeDuration at 1.0 and the LifetimeAlpha calculation in FDeferredDecalPS::SetParameters gets a very ...

Unable to change Actor Coloration View Modes in PIE

UE - World Creation - Worldbuilding Tools - Jul 20, 2025

When in PIE changing Actor Coloration view modes from the viewport visualisation mode [Liit] -> [Actor Coloration] -> ... Does not update correctly when switching view mode and sometimes isn't corr ...

Blueprint actor reference breaks after hot reload

UE - Gameplay - Blueprint - Apr 21, 2016

Reference to a blueprint based on a custom class will break if changes are made to the parent class and a hot reload is performed. Error Displayed added to Callstack section. Workaround: Compiling ...

Multi-User Template Project holds at 95% for a very long time

UE - Editor - Content Pipeline - Datasmith - Importer - Oct 9, 2018

I have now waited over 25 minutes to open the Multi-User project template, and it will not move past 95%.  I have attempted this twice with the same result.  Other templates load without delay. Upd ...

RenderTrace fatal error, shader expected a uniform buffer at slot 1...

UE - Rendering - Architecture - Mar 4, 2024

RenderTrace plugin does not appear to have been updated for a change that moved the GPUScene out of the View buffer to its own uniform buffer. (CL 24027890) The test project is based on FirstPerson ...