Frostbite on Roosters Comb

It’s been so cold in Virginia that it’s been in the single digits at night and strong winds today plus tonight. We have an electric heater in the chicken coop but going put everyone indoors tonight instead of the coop cuz of high winds. I heard putting Vaseline on the comb helps. My fiancé thinks he will loose some of his comb. Is this really bad frostbite or what are some options we can do to help