There’s some instructions on how to use the display viewer here - G'MIC - GREYC's Magic for Image Computing: A Full-Featured Open-Source Framework for Image Processing - Image and Data Viewers
If you press Cntrl+N, it would normalize per channel. However, this isn’t what I want to see first thing. I would want to disable normalization first rather than by channel. Not really a big deal, but doing it twice isn’t ideal.