Shift Key Press stops movement when moving with Arrow Keys

Frequency: Always/Systematic
World name: Gilgamesh
Character name: Aerelia Shinrin
Class/Level: All Classes/Max Level
Party or solo: All situations
In-game time: 2:00pm ET
Area and coordinates: all areas
Housing: n/a
Steps:
1. Move in any direction by holding down an arrow key on the keyboard
2. Press Shift Key

Expected Behavior: Character continues moving.
Current Behavior: Character movement is interrupted by shift keypress. (character movement stops)

- while shift key is pressed, movement can be restarted by pressing arrow key again
- unpressing shift while continuing to hold arrow key down does not resume movement

Specs do not matter, this was tested with gamepad and with keyboard across multiple characters and PCs in multiple locations across the USA. After discovering this I had multiple friends test this out on their systems as well.

It doesn't affect me, but I use WASD for movement. It doesn't affect me regardless of if numlock is on or off. It doesn't even disrupt auto-run for me.

turn off sticky keys