JSFiddle - React, Tailwind, and code Playground

HTML

<ul>
    <li>One</li>
    <li>Two</li>
    <li>Three</li>
    <li>Four</li>
</ul>

CSS

li {
    /* height:50px; removing this fixes it */
    background-color:#eeeeee;
    padding:20px;
    margin:2px 0px;
}

.ui-resizable { position: relative;}
.ui-resizable-handle { position: absolute;font-size: 0.1px;z-index: 99999; display: block; }
.ui-resizable-s { cursor: s-resize; height: 7px; width: 100%; bottom: -5px; left: 0; }

JavaScript

$("ul").sortable({axis:'y'});

$("li").resizable({handles:'s'});