The toString() stringifier method of the DOMTokenList interface returns the values of the token list serialized as a string. The return value is a space-separated list of tokens equal to the DOMTokenList.value property.
toString()None.
A string.
const element = document.createElement("div");
const classes = element.classList;
element.className = "shop empty-cart";
classes.add("logged-in", "dark-mode");
console.log(classes.toString());
// "shop empty-cart logged-in dark-mode"