Pasting into a layer mask changes values
I have a grayscale image in a layer and another layer with a blank / white mask applied. I copy the grayscale image and paste it into the mask, and find other grayscale values, which is a no-go for a software developer. I did not choose the values for fun but because I need exactly these and no others (99% black/RGB 1/1/1 is 100% after pasting / RGB 0/0/0).
I tried it with another document, and by converting everything from RGB to grayscale, but it didn't change anything on this behaviour.
