JSFiddle - React, Tailwind, and code Playground

HTML

<div>
    <p>Select something in here with the mouse. The selection will clear after a second.</p>
    <p>Try it an a text input: <input value="Some text"></p>
        <p>Try it an a text input: <textarea rows="5" cols="30">Some text</textarea></p>
</div>

JavaScript

function clearSelection() {
    var sel;
    if ( (sel = document.selection) && sel.empty ) {
        sel.empty();
    } else {
        if (window.getSelection) {
            window.getSelection().removeAllRanges();
        }
        var activeEl = document.activeElement;
        if (activeEl) {
            var tagName = activeEl.nodeName.toLowerCase();
            if ( tagName == "textarea" || (tagName == "input" && activeEl.type == "text") ) {
                // Collapse the selection to the end
                activeEl.selectionStart = activeEl.selectionEnd;
            }
        }
    }
}

document.onmouseup = function() {
	  window.setTimeout(clearSelection, 1000);
};