“Frosty the Snowman,” the beloved animated holiday classic, airs tonight at 8:30 p.m. Eastern on NBC. The show follows the iconic cartoon adaptation of “How the Grinch Stole Christmas.

Speaking of the holidays, let’s get to the major changes coming to two cartoon Christmas classics: Rudolph the Red-Nosed Reindeer, released in 1964, and Frosty the Snowman, which started airing ...