JSFiddle - React, Tailwind, and code Playground

HTML

<ul id="list">
    <li id="one">one</li>
    <li id="two">two</li>
</ul>

JavaScript

var observer = new(WebKitMutationObserver || MutationObserver)(function(mutations, observer) {
    mutations.forEach(function(mutation) {
        if (mutation.previousSibling !== null) {
            console.log("MutationRecord");
            console.log(mutation);
            console.log("MutationRecord.previousSibling");
            console.log(mutation.previousSibling);
            console.log("MutationRecord.previousSibling.previousSibling");
            console.log(mutation.previousSibling.previousSibling);

            console.log("$(MutationRecord)");
            console.log($(mutation));
            console.log("$(MutationRecord).prev()");
            console.log($(mutation).prev());
            console.log("$(MutationRecord.previousSibling)");
            console.log($(mutation));
            console.log("$(MutationRecord.previousSibling).prev()");
            console.log($(mutation).prev());
        }
    });
});

observer.observe(document, {
    childList: true,
    subtree: true
});

$("#two").prependTo("#list");