JSFiddle - React, Tailwind, and code Playground

HTML

<textarea id="mytextarea" style="height: 200px">
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</textarea>

JavaScript

$("#mytextarea").on('scroll', function() {
    console.log("scrollHeight: " + this.scrollHeight);
    console.log("scrollTop: " + this.scrollTop);
    
    var offset = 200;
    
    if (this.scrollHeight <= (this.scrollTop+offset)) {
        console.log("end of textarea");
    }
});