Camera behavior during "Orbit Pan Mode" (Alt+MMB+Drag) is wrong while piloting an actor

UE - Editor - Developer Usability - Nov 18, 2025

In the Level Editor, dragging the mouse while the "Alt" key is pressed performs one of the "Orbit" movements: OrbitRotation, OrbitPan, OrbitZoom. The same can be done while Piloting an actor. Howev ...

[CrashReport] Mac crash - UE4Editor-SlateCore.dylib!FSlateApplicationBase::Get()

UE - Platform - Apple - Oct 5, 2017

This is a slightly common Mac crash that has occurred since 4.17.1. Users have not provided any descriptions of their actions when the crash occurred. Callstack from Log[2017.10.05-15.00.31:683][3 ...

Crash on attempt to clear(NullifyInstance) of duplicated Hierachial Instanced Static Mesh

Tools - May 31, 2019

When creating an C++ Actor with a Hierarchical Instanced Static mesh. when duplicating such an actor with mesh instances, the instances are not visible on the level. In this state, calling HISM comp ...

[CrashReport] UE4Editor_UnrealEd!FEdGraphUtilities::PostProcessPastedNodes() [edgraphutilities.cpp:138]

UE - Gameplay - Blueprint - Jan 24, 2017

This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Descriptions from users are provided below. Error message: Access violation - code c0000005 ( ...

[CrashReport] UE4Editor-Core.dylib!FTextHistory::Rebuild(TSharedRef<FString,()

UE - Platform - Apple - Aug 15, 2017

This is a trending Mac crash in 4.17.0 that has also occurred with some frequency since at least 4.14. I have not been able to identify any matching callstack occurring on Windows, although it does ...

[CrashReport] UE4Editor_Renderer!FRendererModule::DrawTileMesh() [renderer.cpp:51]

UE - Rendering - Architecture - Materials - Jan 12, 2017

This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Descriptions from users are provided below. Error message: Access violation - code c0000005 ( ...

Map placed actor binding to another actor's Event Dispatcher (multicast delegate) results in duplicate bindings after blueprint recompile

UE - Framework - Blueprint - Apr 17, 2025

Context Blueprint actors placed on the map can bind to another actor's event. If an ActorB has a reference to ActorA, it can bind to an event dispatcher in A by creating an event node in ActorB's e ...

Level Instance Property Override: Actor::Tags overridden pre-CS but clobbered by RerunConstructionScripts with no post-CS re-apply

UE - World Creation - Worldbuilding Tools - May 4, 2026

Summary When using the Level Instance Property Override system, overrides applied to `AActor::Tags` are silently lost for Blueprint actors whose Construction Script assigns or appends to `Tags`. The ...

[CrashReport] Mac crash - FCocoaRunLoopSource::Process

UE - Platform - Apple - Sep 14, 2017

This is a somewhat common Mac crash that has occurred since at least 4.14 and into 4.17. Users have not provided any descriptions of their actions when the crash occurred. The callstack contains l ...

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 ...