I thought it was cucumber joke before I looked at the picture ^.^

Another one who doesn't know how to cook umber. For a brief spell, about 33ms in between these stages, umber becomes dark green with a very light green edge. That's actually where cucumber gets its name, it's shorthand for cooked umber.

The original umber earth pigments were legit made like this, the naturally dark umber was literally burned to turn it reddish brown. However, with modern synthetic replacements, iron can be burned to get the darker iron oxide and chemically oxidized to get the redder version.

Umber is such an old pigment it appears in cave paintings tens of thousands of years old.