In the DragForce module drag amounts greater than one can accelerate the particle instead of slowing it down.

UE - Niagara - Jun 10, 2019

Drag force allows for values greater than 1, which can cause the drag force to exceed the initial velocity, which will continue to compound until a NaN is reached or the particle's lifetime is up. ...

Cannot change Collision Profile of BP component instances

UE - Simulation - Physics - Oct 24, 2019

BP instances placed in level cannot have their components' collision profiles modified to anything other than default and custom. Note that this did not occur in 4.22 (after applying the separate ...

Niagara system loses source emitters when moving Engine from 4.22 or earlier to 4.23 or later.

UE - Niagara - Nov 29, 2019

The following code causes this behavior.// NiagaraSystem.cpp for (FNiagaraEmitterHandle& EmitterHandle : EmitterHandles) { EmitterHandle.ConditionalPostLoad(NiagaraVer); if (!EmitterHandl ...

Simulating forking bones ignores import scale

UE - Simulation - Physics - Dec 12, 2019

Simulating the children bodies, but not the parent, of a skeletal mesh imported with a uniform scale not equal to 1, seems to ignore the imported scale, instead using their initial relative location ...

USD Stage is not available on Mac and Linux

UE - Editor - Content Pipeline - Import and Export - Dec 17, 2019

On Mac and Linux the option to open the USD Stage window is not there like it is on Windows. This is not a regression since USD Stage was not preset in 4.23.1 (CL-9631420) on any platform. ...

Attached actor in Sequencer does not detach regardless of the detach state settings until Sequencer is restarted

UE - Anim - Sequencer - Jan 29, 2020

Attached objects in sequencer do not detach with newly specified "When Finished" property until Sequencer is restarted.  Tested in: 4.23.1 CL#9631420  4.25 CL#11062379 ...

Problems in skeletal mesh merge

UE - Editor - Content Pipeline - Asset Build - May 10, 2021

There are a few issues a licensee has found with the skeletal mesh merge operation. See the UDN for more details and the proposed fixes. Note, the issue with the cloth merge is already logged in a ...

Size input box too narrow in UMG Widget Editor

UE - Editor - UI Systems - Jan 24, 2022

Only 2 digits are visible in the size box that holds values between 1.0 and 0. Meaning most values will contain 3 digits. This is different from UE4 where more digits are visible. ...

bIgnoreAllPressedKeysUntilRelease only applies to keys in the previous mapping

UE - Gameplay - Input - Jun 16, 2022

This is because the RebuildControlMappings function only checks this flag when you have a mapping that was already added, we should apply this for any new mappings as well.  I'll update the repro s ...

shared texture sampler doesn't work in mobile

UE - Platform - Mobile - Jan 5, 2023

In mobile preview or android device in 5.1 release, M_SharedTexture_Inst material does not render properly due to exceeded sampler slot limit. there was no problem in 5.0.3 ...