Idea: It'd be great to be able to open multiple tabs side-by-side. For me, I'd especailly find it useful to open the "Edit" and "Info" tabs at the same time. I find that during my culling process, I often click back and forth between them - in "edit" I'm checking the histogram and in "info" I'm often double checking if the image is a JPEG vs. RAW.
I could see there being value in being able to do the same for something like "Edit" and "Masking" both open side by side to see how individual masking changes also affect the histogram of the image as a whole. Or "Edit" and "Crop" for the same reason - as you adjust the crop, how is it affecting the image histogram (i.e. impact of cropping out highlights or shadows).
Rough mockup shown below of both "Edit" and "Info" being open side by side.
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