If you click in the upper area (shown by the oval), you can drag the region between the markers, left or right. You can also drag each marker separately from here… BUT, there’s no readout of the frequencies being set (lower area rectangle) .!
You have to hover over the lower controls to display this data.
It would just be clever and neat if the frequency readouts (both together.!) became visible when using the upper markers/range finder window too.
Put it another way, why bother allowing the mouse to be used to change the range or lower/upper limits in the little graphical window at all, if you can’t tell what frequencies you’re setting…?
Ok, ok… its not rocket science, I know…! But, its the attention to detail; its the TLC. People are making a load of effort coding all this stuff; here’s just a little suggestion to help complete the ergonomics.
BTW - All these Channel Strip plugins are nice/useful tools…! 