EDITOR: LIVE: CRASH: Reroute nodes can cause a loop that freezes the editor.

UE - Gameplay - Blueprint - Jul 29, 2014

Branch Build Label UE4-Main Promoted-CL-2230001 DESCRIPTION: If reroute nodes are used to make a loop, the editor will not catch it and the loop will freeze the editor. ADDITIONAL NOTES: Creatin ...

Crash when changing a Play Node's "Sequence" to a Montage

OLD - Anim - Jan 20, 2016

I understand that this is not something you're intended to be able to do (Montages aren't used this way), but we should bar the user from inserting a montage into this variable slot. Crash occurs w ...

[CrashReporter] Crash in FAnimNode_StateMachine::Evaluate()

OLD - Anim - Aug 22, 2016

This JIRA was created as a result of it being one of the top crashes occurring in 4.13 Preview 2 Error message: Access violation - code c0000005 (first/second chance not available) Source Context ...

Sprite sheets cannot be reimported in 4.8 in a project that was converted from an older version

UE - Gameplay - Paper2D - Jun 11, 2015

User bug report: Why do you guys remove the Json Importer from UE 4.8? All atlases from TexturePacker can not be imported anymore on our projects. Is there a way to activate it? or maybe is there a ...

Niagara color picker user parameter preview no longer updates until confirmation

UE - Niagara - Apr 18, 2025

Starting with UE 5.4, the Color Picker Tool no longer updates preview values in real time for certain editor windows like Niagara when working with User Parameters. This behavior is a regression fr ...

[CrashReport] UE4Editor_UMG!UButton::SynchronizeProperties() [button.cpp:62]

UE - Editor - UI Systems - Sep 7, 2017

This is an infrequent but longstanding crash that has occurred since at least 4.13 and affected more than 350 users. User DescriptionsI using widget bp. I Try moving blur mistake same time press ct ...

FMultiReaderSingleWriterGT isn't thread safe

UE - Foundation - Core - May 17, 2016

From https://udn.unrealengine.com/questions/292741/fmultireadersinglewritergt-isnt-thread-safe.html: I've found that FMultiReaderSingleWriterGT has at least 2 bugs: The one that caused a deadlock ...

Reversed Animations don't play properly using Skeletal Mesh Pose and animations with Keep State in Sequencer

UE - Anim - Sequencer - Nov 26, 2018

The bug seems to only reproduce when setting animations in sequencer and only if the animations are set to "Keep state". Setting them to "restore default" makes the reversed animation play correctly ...

Physics Asset details window jitters when shrunk.

Tools - Sep 29, 2014

Branch Build Label UE4-Main Promoted-CL- 2306964 DESCRIPTION: When using the vehicle template and having any wheel selected inside the physics asset, shrinking the size of the details window ca ...

Creating a copy of BSP after fliping it in geometry edit mode cause the copy to be invisible

UE - LD & Modeling - Modeling Tools - BSP - Aug 29, 2014

Branch Build Label UE4-Main Promoted-CL- 2270796 DESCRIPTION: If a player goes into geometry edit mode and flips a bsp then makes a copy of it the copy will appear invisible ADDITIONAL NOTES: A ...