title: TypeError: $.ajax is not a function
body: <p>Obviously I need to elaborate. <strong>Every single function even ones that can be replaced by vanilla JS, are jQuery functions that work, but the AJAX function does not work.</strong></p>
  
  <pre><code>$.ajax({
      type: "POST",
      data: {
          email: emailInput,
          mode: 0
      },
      url: "main.php",
      cache: false
  }).done(function(response) {
  
  });
  </code></pre>
  
  <p>I tried it without promises, I tried it as $.post, I tried everything but it doesn't work.</p>