JSFiddle - React, Tailwind, and code Playground

HTML

<p>The quick brown fox</p>

CSS

p {
    font-family: userfont, Courier, monospace;
}

JavaScript

function setUserFont(fontName) {
	const userFontFace = new FontFace('userfont', `local(${fontName})`);
	document.fonts.add(userFontFace);
}

setUserFont('Arial');

/* setUserFont('non existant'); // <-- Try uncommenting with "ctrl+/" */