In Singapore, it's quite common to use "staff" for a single person, and not uncommon to use "staffs" as a plural. For example, from a local university's press release:
In US English this would be incorrect, and Merrian-Webster notes that expected plural of "a member of staff" is simply "staff". Is this considered correct in any other variety of English?
(As a parenthetical note, this type of confusion around irregular plurals is fairly common in Singapore, because the majority of the population is of Chinese origin and Chinese doesn't really have plurals in the English sense.)