Duplicating a blueprint that implements an interface and then removing that interface will cause compile errors that don't occur if the interface was removed from the original BP

UE - Gameplay - Blueprint Editor - Aug 1, 2020

See steps to reproduce. Looks like the fixup when saying Yes to "Would you like to transfer the interface functions to be part of your blueprint" doesn't work correctly on the duplicated BP. Inter ...

Custom node not working with material attributes

UE - Rendering Architecture - Materials - Jul 15, 2024

Using Material Attributes as an input to a Custom Expression causes the HLSL Translator to create multiple CustomExpression# functions, for each used member of the Material Attributes, rather than u ...

Using a Macro to access a variable from another Actor causes a crash in Standalone

UE - Gameplay - Blueprint - Jun 8, 2015

Using a Macro to access a variable from another Actor causes a crash in Standalone. This does not seem to affect any other preview in editor, nor packaged games. Reproduced in 4.7.6, 4.8 Preview 4, ...

The Add node does not update in the Construction Script

UE - Gameplay - Blueprint - Feb 28, 2015

The Add node does not update in the Construction Script. Reproduced in 4.7.1 binary and Main (//depot/UE4/Promotable-CL-2455917) ...

RepNotify variables passed by reference to a function or macro that then change the value of the variable do not trigger the OnRep function on the Server

UE - Networking - Jul 1, 2015

RepNotify variables passed by reference to a function or macro that then change the value of the variable do not trigger the OnRep function on the Server. This is inconsistent with the behavior with ...

Illegal Else Without Matching If

UE - Simulation - Physics - Feb 3, 2017

Looks like there's a missing if/else pair in BodyInstance.cpp ...

Particle record in the Matinee leads to crash when playing after record.

Tools - Oct 19, 2017

Particle record feature in the matinee seems not properly working in the Editor. When trying to play in the matinee with recorded keys, the Engine will crash with Access violation - code c0000005. ...

Adding to Struct causes 'Inappropriate Outermost' warnings

UE - Gameplay - Blueprint - Jun 2, 2015

Adding to Struct causes 'Inappropriate Outermost' warnings to be spammed to the Output Log ...

Increment and decrement nodes return the incorrect value

UE - Gameplay - Blueprint - Jun 23, 2015

Increment and decrement nodes return the incorrect value User Description: Getting the result of the Increment Macro seems to be incrementing the variable twice. Very confusing. Is this normal? ...

Sound Mix Modifiers do not properly affect Sound Class

UE - Audio - Mar 30, 2015

Sound mixers do not properly override variables within a sound class. This prevents users from being able to modify variables such as volume or pitch quickly and efficiently by using the push/pop st ...