I hadn't really thought of either of those useful aspects. Both points in favor of newsprint. It isn't a miracle material but it has a lot of uses.

Old time hobos used newsprint, wrapped around the body underneath your clothes, to increase the insulation. the trick is to crumple and then reflatten each piece individually before tucking it in. It softens and fluffs the paper a bit and the resulting wrinkles don't line up between the sheets so you end up with lots of little air pockets that increase the insulation value.

Six or seven layers worked this way and tucked flat into a trash bag,to keep the paper dry, makes a ground pad that goes a long way to keeping you warm even if you have to sleep on snow.

A few layers worked in the same way and cut to size and used as an insole can go a long way to keeping your feet from freezing if your caught in the woods with shoes more adapted for street use.

Related: Sandwich bags put over your socks and just covering the toes can help keep your toes from freezing without causing you to sweat. Which might defeat the purpose.

On the fun side once caught in an extended rainstorm and pretty much confined to tents I tore up the paper finely and mixed in a little rainwater and some pancake mix for binder. We had fun making papermache figures and drying them over the stove while making supper.

I suspect that the same paper mush might make a good base for a poultice. I would use a strong tea of the active ingredient as the liquid and hold it in place with a bandage or cloth.