IFF radar button gets stuck with joystick assign

[stray cat]

When pressing the IFF button on the radar the following thing happens:

 

1. pressing it with mouse in the cockpit, the button depresses and unpresses when the mouse is let go. I suppose that is the default behaviour.

 

2. When pressing a joystick assigned key, the button stays depressed.

 

However on both times the functionality remains the same, the targets are IFF checked and are reset after a few seconds, so it is just a visual bug.