Increase refresh rate precision from 1 to 2 decimal places in combo box

xfce4-display-settings 4.16.2

xrandr prints the refresh rates 60.00, 60.02, 50.00 and 48.01. The problem is that in Xfce display settings it is impossible to distinguish 60.00 from 60.02 because Xfce is showing 1 decimal place. Please see the screenshot below.