Hello again! I was playing around with 6bd8b84, and am really liking the improvements. I will share a few thoughts if they are helpful:

• Dragging only works when the mouse pointer is inside the hue or value vs saturation field. When the mouse pointer moves outside of it, dragging stops. This makes it annoying when trying to adjust along the achromatic axis or when adjusting hue.
• Hue resets back to Red / 0 when saturation is 0. This is annoying when trying to tune in a saturation of a specific hue close to achromatic and it keeps resetting. And when it resets you can't drag the hue slider anymore, until you drag in the value vs saturation field.
• Currently it's not possible to specify values over 1, which may be desirable with scene-referred grading operators.
• HSV sliders might be more desirable than RGB sliders at the bottom for some tools. Maybe it could be possible to have an option in the widget to select which style is shown? (I'll paste some code I was testing to do HSV slider widgets instead of rgb here - for around like 246 in render_darkroom.h)

        // Testing HSV ColorPicker
        float hsva[3];
        nk_colorf_hsva_fv(hsva, *val);
        hsva[0] = nk_propertyf(ctx, "#H:", 0, hsva[0], 1.0f, 0.01f, 0.001f);
        hsva[1] = nk_propertyf(ctx, "#S:", 0, hsva[1], 1.0f, 0.01f, 0.001f);
        hsva[2] = nk_propertyf(ctx, "#V:", 0, hsva[2], 2.0f, 0.01f, 0.001f);
        *val = nk_hsva_colorfv(hsva);
        nk_combo_end(ctx);

Here's a screenrecording which explains everything in context if it's helpful: