Unicode has four main normalization forms. Their codes are
NFKD. Wikipedia has a good explanation of the topic.
normalize() method returns the string normalized according to the form you specify, which you pass as parameter (
NFC being the default if the parameter is not set).
I will reuse the MDN example because I’m sure there is a valid usage but I can’t find another example:
'\u1E9B\u0323'.normalize() //ẛ̣ '\u1E9B\u0323'.normalize('NFD') //ẛ̣ '\u1E9B\u0323'.normalize('NFKD') //ṩ '\u1E9B\u0323'.normalize('NFKC') //ṩ