Insanely bad performance of the in-engine plugin

General Issues & Bug Reporting (Fab)
1

Summary

The UI performance of the in-engine FAB plugin is somehow even worse than the notoriously abysmal performance of the Bridge plugin.

What type of bug are you experiencing?

UI/Tools

Steps to Reproduce

  1. Install FAB plugin for UI
  2. On high end PC, attempt to scroll using middle mouse button clicking, mouse wheel, or attempt to open and close sidebar.

Expected Result

UI performance is acceptable

Observed Result

UI performance is insanely bad. Scrolling is laggy and jerky, often frezes for multi-second increments. Sidebar open/close animation runs at single digit framerates.

Platform

UE FAB plugin

Operating System

Windows 11

Additional Notes

RTX 2080Ti, latest drivers
Ryzen 3900x
64GB RAM
Engine installed on SSD
No CPU/GPU intensive background tasks running

2

Here’s a video comparison of FAB in chrome vs FAB in engine.

You can see that in the browser, fab runs smoothly, instantly and doesn’t freeze. In engine, fab scrolling first starts lagging and then stops responding completely after few subsequent scrolls. Everything runs at extremely low FPS, including UI animations such as opening/closing the sidebar, and UI elements often respond only on second or third click.