Performing a Hot Reload after changing a UPROPERTY from BlueprintReadWrite to BlueprintReadOnly results in the variable not being shown in context sensitive search results in the Event Graph.

UE - Gameplay - Blueprint - Mar 3, 2015

Changing a UPROPERTY value from BlueprintReadWrite to BlueprintReadOnly, or vice versa, and performing a Hot Reload results in the variables not being found in the Blueprint's Event Graph context se ...

Huge performance hit when recording a demo (demorec)

UE - Networking - Jun 3, 2019

The current engine version (4.22) seems to suffer a huge performance hit when using the demo recording (demorec) feature. This issue is present in both the editor and the packaged game (developer bu ...

"Allow Sequencer Edits Only" and Control Rig performance impact

zComponent - Archive - Mar 27, 2026

We noticed an issue working in sequencer with "Allow Seqeuncer Edits Only" and control rigs. Performance will drop when manipulating using the AnimDetails channel sliders. ...

LandscapeMountains demo has large performance drops at various locations around map

Docs - Samples - Dec 2, 2014

Landscape Mountains experiences heavy performance drops at various locations on map, specifically around ice lake in middle of map or when crashing. FPS varies from 50 FPS down to 11 FPS. ...

Editor Performance drops when removing frames from animations with curve data

OLD - Anim - May 26, 2016

Editor Performance drops when removing frames from animations with curve keys Regression: No, removing frames on animations with curves had a chance to crash the editor in 4.11, which doesn't happ ...

Performance drop when spawning AI actors during runtime compared to placing them in world

UE - AI - Jan 9, 2019

There is a performance difference between spawning and placing AI into a level. This is causing issues when spawning/despawning AI actors in a large open world, where 4-5ms of frame time quickly bui ...

Shadow casting still considered for performance when light intensity set to 0.0

UE - Graphics Features - Sep 8, 2016

Shadow casting is still considered when the lighting intensity has been set to 0. This is a regression in performance from 4.12.5 where a lights intensity that was set to 0 would not be considered ...

Hot reload can no longer be performed after adding an empty class to a Blueprint-only project

UE - Foundation - Core - Feb 7, 2019

Adding an empty code class to a Blueprint-only project prevents the project from being able to perform any hot reloads. When clicking the Compile button in the Editor, a warning is added to the log ...

Performing a Clean on a project using a binary Engine installation on Mac removes some Engine .dylib files

UE - Foundation - Core - May 17, 2018

When a Clean is performed on a code project that uses a binary Engine installation on a Mac, some of the Engine's .dylib files are removed during the Clean process. A Clean process for a project usi ...

Using High Resolution Screenshot while the viewport is in Full Screen causes massive performance issues after the screenshot is successfully taken until the Editor is restarted

UE - Graphics Features - Jan 6, 2022

This is a regression. Maybe Binary only if it hasn't already been fixed. Tested in:StreamCLTypeResults//UE5/Main18386535PerforcePerformance is normal after screenshot//UE5/Main18218925Perforce Per ...