JSFiddle - React, Tailwind, and code Playground

HTML

The red div will follow you on screen when you scroll and the anchor point div is out of the viewing area: <br /><br />
<div id="anchor" style="left: 150px; border: 0px;">Anchor point for follow div</div><div id="follow">Follow on scroll</div>

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Bottom of page.....

CSS

div {
    border: 1px solid red;
    display: inline-block;
    position: absolute;
    top: 100px;
}

JavaScript

$(window).scroll(function () {
    if (! isScrolledIntoView($('#anchor')))
    {
        // anchor div isn't visible in view so apply new style to follow div to follow on scroll
        $('#follow').css({ position: 'fixed', top: '10px' });
    }
    else
    {
        // anchor div is visible in view so apply default style back to follow div to place in default position
        $('#follow').css({ position: 'absolute', top: '100px' });
    }
});

function isScrolledIntoView(elem)
{
    var docViewTop = $(window).scrollTop();
    var docViewBottom = docViewTop + $(window).height();

    var elemTop = $(elem).offset().top;
    var elemBottom = elemTop + $(elem).height();

    return ((elemBottom >= docViewTop) && (elemTop <= docViewBottom));
}