Some hens will pluck themselves when they are laying. They don't have to be broody when they do this just laying, if you are worried you can check her over for parasites, otherwise there are places on chickens where there is no feathers, under their wings is one.
She may be eating her own feathers for the protein....do you see any feathers around the coop and run?
Layer pellets are usually minimal protein(~16%) needed to lay....the other foods dilute that protein level.
I like to feed a 'flock raiser' 20% protein crumble to all ages and genders, as non-layers(chicks, males and molting birds) do not need the extra calcium that is in layer feed and chicks and molters can use the extra protein. Makes life much simpler to store and distribute one type of chow that everyone can eat. I do grind up the crumbles (in the blender) for the chicks for the first week or so.
The higher protein crumble also offsets the 8% protein scratch grains and other kitchen/garden scraps I like to offer. I adjust the amounts of other feeds to get the protein levels desired with varying situations.
Calcium should be available at all times for the layers, I use oyster shell mixed with rinsed, dried, crushed chicken egg shells in a separate container.
Animal protein (mealworms, a little cheese - beware the salt content, meat scraps) is provided during molting and if I see any feather eating.