Fab UE Plugin does not respect UI Scale editor preference

Summary

In the UE Editor, starting with version 5.4, there is a very useful UI Scale setting in the general page of the Editor Preferences. The new Fab plugin does not appear to recognize or respect this setting and behaves as if the setting is 1.0.

Context: I run on a pair of 4K monitors, on Linux, and am starting the engine with the “-nohighdpi” command line parameter because otherwise the editor tries to scale based on the (reported) physical size of the monitors, which are different. I don’t know if this bug is reproducible without the “-nohighdpi” option.

What type of bug are you experiencing?

Plugins

Steps to Reproduce

  1. Install and enable the Fab plugin in UE 5.4.x (I am running 5.4.3).
  2. Start the engine with the “-nohighdpi” command flag (this flag may not be required).
  3. Set the UI Scale in the Editor Preferences to a value other than 1.0 (I use 1.8).
  4. Open the Fab window from the menu, either docked or free-floating.

Expected Result

All of the Unreal Editor windows and tabs should be scaled according to the UI Scale setting.

Observed Result

All UE Editor windows and tabs are properly scaled except the Fab window, which remains at the default scale.

Platform

Unreal Editor prebuilt, 5.4.3

Operating System

Linux 64-bit

Additional Notes

The issue is reproducible with the Fab window docked or floating, and with it on either of my two monitors.