RGB levels histogram?

Hi. My question is to do with adjusting curves for DSLR-scanned colour-negatives.
In photoshop if I open up the curves for each RGB channel I can invert them separately and there is a little histogram on the curves graph showing me where i need to drag my light and dark points in order to get the colour correct.
Now I can do the same thing in RawTherapee but the little histogram isn’t there so when I’m inverting each colour channel I basically have to guess where the points should be, making it extremely difficult to get accurate inversion and correct colours.
Anyone know if it’s possible to get this feature in RawTherapee?
Thanks

Background histograms have not yet been implemented for some curves:

Adding your voice to that issue might help.

Thanks Morgan. I’d be happy to do so.
All the best