The read-only relList property of the HTMLLinkElement returns a live DOMTokenList object containing the set of link types indicating the relationship between the resource represented by the <link> element and the current document. It reflects the <link> element's rel content attribute.
A live DOMTokenList object.
Although the relList property itself is read-only in the sense that you can't replace the DOMTokenList object, you can still assign to the relList property directly, which is equivalent to assigning to its value property. You can also modify the DOMTokenList object using the add(), remove(), replace(), and toggle() methods.
const links = document.getElementsByTagName("link");
for (const link of links) {
console.log("New link found.");
link.relList.forEach((relEntry) => {
console.log(relEntry);
});
}<a> and <area>, HTMLAnchorElement.relList and HTMLAreaElement.relList.HTMLLinkElement.rel