title: includes() not working in all browsers
body: <p>right here is a block of my code. It works perfect in fireFox and Chrome. But not in IE. I get the error "<code>Object doesn't support property or method 'includes'</code>"</p>
  
  <pre><code>function rightTreeSwapfunc2() {
      if ($(".right-tree").css("background-image").includes("stage1") == true) {
          $(".right-tree").css({
              backgroundImage: "url(/plant-breeding/img/scenes/plant-breeding/stage5.jpg)"
          })
      } else {
          $(".right-tree").css({
              backgroundImage: "url(/plant-breeding/img/scenes/plant-breeding/stage3.jpg)"
          })
      }
  }
  </code></pre>
  
  <p>I could change it up a bit and use vanilla JS and do:</p>
  
  <p><code>document.getElementById("right-tree").classList.contains</code></p>
  
  <p>But I would rather see if there is a way to get it to work in IE before changing the JS and editing the HTML and CSS. </p>