JSFiddle - React, Tailwind, and code Playground

HTML

<div>
    <p>Hello World<sup><a href="#footnotes_1" id="link_back_1">1</a></sup></p>
    <p>Hello World<sup><a href="#footnotes_2" id="link_back_2">2</a></sup></p>
    <p>Hello World<sup><a href="#footnotes_3" id="link_back_3">3</a></sup></p>
    <ol>
        <li>[<a href="#link_back_1" id="footnotes_1">1</a>] Footnote 1</li>
        <li>[<a href="#link_back_2" id="footnotes_2">2</a>] Footnote 2</li>
        <li>[<a href="#link_back_3" id="footnotes_3">3</a>] Footnote 3</li>
    </ol>    
</div>

CSS

div {
    height: 300px;
    overflow: scroll;
}
ol {
    margin-top: 800px;
    list-style-type: none;
}