In the “General” tab of Preferences there is an option to:
“Use working profile for main histogram and Navigator”
Left unselected, what profile is used for the main histogram and Navigator?
What are the advantages to selecting this option?
Yes, I did check RawPedia. No mention of this option there. Perhaps because I am using a very new version (730). of RT?
@mikesan Doesn’t a tooltip show when you hover above this setting?
Thank you. I guess I didn’t hover long enough.
The tooltip tells me that, when this option is not checked, the gamma corrected output profile is used for the histogram and Navigator. Now I need to know which option is recommended and under what circumstance. In other words, how should this choice influence my interpretation of the histogram?
The recommended option is the default option - disabled. This is because you generally want to see the histogram and RGB values of the image the way it will be once its saved. When enabled, you see the histogram and the RGB values of the image before it gets converted into the output space. I can’t think of a practical example why you would want to do that, but I’m sure one exists since it’s been implemented 
Thanks for that clarification. Appreciate your help.
Digging a bit, I find the following in RawPedia, under Curves:
The curve and histogram is always displayed with sRGB gamma, regardless of working or output profile. This means that the shadow range is expanded and highlights compressed to better match human perception.
Is this true of the “general” histogram, or does it apply only to the histogram displayed as background in the curves panel?
I was told last year (probably when I wrote that) that it applies to the curve’s axes and the histogram behind the curve. Note we’re talking about sRGB gamma, which is not the same thing as the sRGB working space.