GameInstance and subsystem initialization order is incorrect for Play In Editor

UE - Gameplay - May 18, 2023

The order of world and game instance initialization is different between a true standalone game (cooked game or an editor build with -game) and a Play In Editor game. Specifically, in Play in Editor ...

[CrashReport] UE4Editor_SlateCore!IsResourceObjectValid() [drawelements.cpp:23]

Tools - Aug 2, 2018

No user comments in crash group 18 FSlateShaderResourceManager* FSlateDataPayload::ResourceManager; 19 20 static bool IsResourceObjectValid(UObject*& InObject) 21 ...

editor crashes when variable inside of a struct is set to a class type then the object is moved to a new folder

UE - Gameplay - Blueprint - Mar 17, 2015

If a struct has a variable set to a class type, then the object of that class type is moved to a new folder in the editor, the struct will replace the class type with "class", which causes the edito ...

Pre-UE5 serialized FVariant FVector data corruption when deserialized in UE5

UE - Framework - LWC - Jan 15, 2024

FVariant is a struct that implements a union of data types, including FVector. When assigning an FVariant an FVector value in engine versions UE 4.27 or earlier, the FVariant will deserialize incorr ...

Calling UBlueprintMapLibrary::GenericMap_Find with a non-existent key causes a memory leak

UE - Framework - Blueprint - Apr 15, 2025

When Calling UBlueprintMapLibrary::GenericMap_Find with a non-existent key, the function construct the default structure in-place on the given pointer without destroying the object. This behavior ca ...

[AI] Debug Render Scene Proxy hits ensure for registering a delegate twice during level streaming.

UE - AI - Debugging - Aug 31, 2022

Description from licensee: We're seeing an ensure get tripped up in FDebugRenderSceneProxy that says "DrawDelegate is already Registered!". Debugging the issue, we have confirmed that the DrawDeleg ...

Chaos : Rigid body sleeps when very small external force is applied by AddForce

UE - Simulation - Physics - Solver - May 25, 2022

When a small external force is applied to the rigid body, the VSmooth value is reset in the ResetVSmoothFromForces function. Since this function ignores the current velocity, a very small velocity ...

[CrashReport] Assertion failed: !PinRef->bWasTrashed | UEdGraphPin::SerializePin()

UE - Gameplay - Blueprint - Aug 29, 2017

This is a common and longstanding crash that has occurred since at least 4.15 and affected nearly 500 users. The CrashGroup was previously linked to [Link Removed], but that had specific repro step ...

Typo in "BaseEditorSettings.ini": under section [/Script/UnrealEd.ContentBrowserSettings], key "DisplayPluginFolder" (singular) should read "DisplayPluginFolders" (plural).

UE - Editor - Workflow Systems - Oct 11, 2025

File "<ENGINE_PATH>/Engine/Config/BaseEditorSettings.ini" contains the following setting: [/Script/UnrealEd.ContentBrowserSettings] ; Whether to display the game project plugins in the Content Brow ...

Crash when resizing window using Quad Stereo Buffer

UE - Virtual Production - nDisplay - Oct 2, 2019

We noticed crashes in our application when we attempted to resize a window or switch to full-screen mode. Hence, resizing windows and switching to full screen will result in a crash on Unreal Engine ...