Easily and safely escape HTML in one line

x => Object.assign(document.createElement('div'), { textContent: x }).innerHTML

True, you could also do it with

x => x.replace(/&/g, "&amp;").replace(/</g, "&lt;").replace(/>/g, "&gt;").replace(/"/g, "&quot;").replace(/'/g, "&#039;")

or similar, but if you do it the first way you don't have to remember the HTML entities 🙂