Pasting timeline components into another actor and then choosing "cancel" on fix self context function references results in a broken state

UE - Framework - Components - Sep 13, 2021

upd. Regression was checked on //UE4/Release-4.26 CL 15973114, issue was reproduced. Regression - No ...

Crash on garbage collection - Encountered 20 object(s) breaking GC Clusters assumptions.

UE - Foundation - Core - Aug 15, 2018

Garbage collection crash during opening cinematic. Note after crashing and relaunching the game the saved file appears as 8% complete instead of 0%. Note this crash is also occurring with //UE4/D ...

Instanced meshes velocities fix

UE - Graphics Features - Sep 21, 2016

"We've been able to enable velocity rendering when using instanced rendering. However, by looking at the generated vertex shader the computation of the previous position seems to be incorrect: flo ...

Fix world to meters scale

UE - Platform - XR - Apr 11, 2018

Is changing the world to meters in the current 4.19 AR template project supposed to affect the world, or is world to meters only for VR projects currently? We have project where a client wants us to ...

Integrat PhysX crash fixes

UE - Simulation - Physics - Solver - Aug 24, 2021

Sequencer frame range progression is not continuous

UE - Anim - Sequencer - Oct 28, 2021

The end of the level visibility section places a DeterminismFence. This causes the issue. The fence clips the frame range and produces a discontinuous frame ranges, e.g. 23201~24000, then 24001~24 ...

Crash occurs when diffing blueprint that has had one of its variables changed to a Soft Object Reference

UE - Gameplay - Blueprint Editor - Oct 3, 2017

A crash occurs when diffing a blueprint that contains an array that has changed from an Object Reference to a Soft Object Reference. Note: I figured that this could be related to another bug that I ...

[CrashReport] Assertion failed: NewWorld | UE4Editor_Engine!UEngine::LoadMap()

UE - Gameplay - Nov 2, 2017

This is a common and longstanding crash that has occurred since at least 4.15. Originally this was being tracked under [Link Removed] due to sharing the same callstack, but that had specific repro ...

Niagara Data Interface "Errors and Warning" section on Module Details not updating when error messages change

UE - Niagara - Aug 14, 2025

This is a regression: it worked correctly up to UE 5.5, but not in 5.6 or mainline latest. Possibly caused by CL 40093049. Class UNiagaraDataInterface provides virtual method GetFeedback(), which a ...