JSFiddle - React, Tailwind, and code Playground
JavaScript
var el1 = document.createElement('div');
el1.setAttribute('contenteditable',true);
el1.style.cssText = "width: 400px";
el1.innerText = "Я блок!";
document.body.appendChild(el1);
var el2 = document.createElement('b');
document.body.appendChild(el2);
el2.innerText = "blo blo";
el2.previousSibling.innerText = "";
el2.previousSibling.focus();