add syntax highlighting to Qase

qasegherking.user.js

// ==UserScript==
// @name         Qase Gherkin
// @version      0.1
// @description  add syntax highlighting to Qase
// @author       github.com/foso
// @match        https://app.qase.io/run/*
// @match        https://app.qase.io/case/*
// @match        https://app.qase.io/project/APP20*
// @icon         https://qase.io/favicon.png
// @grant        none
// ==/UserScript==

var oldText = "";

var observer = new MutationObserver(function (mutations, me) {
 
  var editorContent = document.querySelector('.toastui-editor-contents');
  if (editorContent) {
      var newText = editorContent.innerHTML;
      if(newText !=oldText){
          editorContent.innerHTML = editorContent.innerHTML
            .replaceAll("And ","<span style=\"color:blue;font-weight:bold\">And</span> ")
            .replaceAll("But ","<span style=\"color:blue;font-weight:bold\">But</span> ")
            .replaceAll("When ","<b>When</b> ")
            .replaceAll("Given ","<b>Given</b> ")
            .replaceAll("Then ","<b>Then</b> ")
            .replaceAll("Scenario: ","<b>Scenario:</b> ");
          oldText = newText;
      }

    return;
  }
});

// start observing
observer.observe(document, {
  childList: true,
  subtree: true
});