A drop-down menu with too many items can overflow the screen, e.g. low resolution & many items. The screenshot shows network interface selection: https://0x0.st/-E4Y.gif

Tixati 2.84 on Windows

I don't know what the hell are you doing with 10+ network interfaces, but you may solve your very edge case in 2 ways:
- Go to Windows' Display settings and set the orientation from Landscape to Portrait temporarily, select your desired interface if it fits on your display, then set it back.
- After clicking on the ... to select the interface, use your up and down arrow keys to select the ones not visible on the screen, press enter and see if is the right one is put in the manually editable field.