What is mason root beer?

As an AI language model, I do not have access to current information, but as per historical sources, Mason Root Beer was a brand of root beer that was popular in the early 20th century in the United States. It was named after the founder of the company that produced it, Charles Mason, who started manufacturing soda in 1852. Mason Root Beer was praised for its smooth, creamy, and frothy texture, which made it stand out from other root beers of its time. The recipe of Mason Root Beer included sarsaparilla, wintergreen, and licorice, which gave it a unique flavor. The company stopped production of Mason Root Beer in the mid-20th century, and it is no longer available in the market. However, some people still remember it as one of the best root beers they ever tasted.