title: Only fire form submit when form has 'success' class
body: <p>I'm trying to configure a form submission trigger to only fire when a <code>success</code> class is present in the main form tag. The class is added when the form is valid but it is not captured in the Form Classes GTM variable when the form is submitted. How can I get the form submit to wait until the success class has been added to the form element?</p>
  
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