Custom Size Animated Gif Issue

Steps to reproduce:
1. Create a sequence to export as animated GIF

2. Export

3. Choose Animated GIF

4. Choose a standard frame size

5. Click "Custom Size" and lock proportions

6 Enter a horizontal dimension and start typing "400"

Result: ...First digit (typing "4") flips to a 1. Cannot start with 2, 3, 4 or anything else. Maximum small size is 199. Can go to 4 digits, but that's too big for the icon I want to create.

Expected: To be able to enter any size I want.
 
System info
    Application: Premiere Pro (Beta) v24.0.0.30
    OS: Windows v10.0.22621, RAM: 63.83 GB GB, CPUs (logical): 16