title: Contact Form 7 Change Form-Tag Output
body: <p>I'm trying to change the output of contactform7 forms from</p>
  
  <pre><code>&lt;form action="/#wpcf7-f583-p294-o1" method="post" class="wpcf7-form"&gt;
  </code></pre>
  
  <p>to</p>
  
  <pre><code>&lt;form action="/#wpcf7-f583-p294-o1" method="post" class="small-12 column wpcf7-form" novalidate data-abide&gt;
  </code></pre>
  
  <p>Therefore I've added some hooks</p>
  
  <pre><code>add_filter('wpcf7_form_class_attr', function($html_class) { return 'small-12 column ' . $html_class; }); // adds respsonsive classes to the form-tag
  add_filter('wpcf7_form_novalidate', function($support_html5) { return true; }); // adds novalidate-attr to the form-tag
  </code></pre>
  
  <p>So the only thing I'm missing is the data-attribute. Is there any hook or any idea, how to get there, without toching the core-Files?</p>
  
  <p>I've found the magic in /contact-form-7/includes/contact-form.php starting in line 297</p>
  
  <pre><code>/* Generating Form HTML */
  public function form_html( $args = '' ) { // ...
  </code></pre>
  
  <p>and then, from line 409 on</p>
  
  <pre><code>$enctype = apply_filters( 'wpcf7_form_enctype', '' );
          ...
  
          $atts = array(
              'action' =&gt; esc_url( $url ),
              'method' =&gt; 'post',
              'class' =&gt; $class,
              'enctype' =&gt; wpcf7_enctype_value( $enctype ),
              'autocomplete' =&gt; $autocomplete,
              'novalidate' =&gt; $novalidate ? 'novalidate' : '',
          );
  
          ...
          $atts = wpcf7_format_atts( $atts );
  
          $html .= sprintf( '&lt;form data-abide %s&gt;', $atts ) . "\n";
          ...
  
          $html .= '&lt;/form&gt;';
          $html .= '&lt;/div&gt;';
  </code></pre>
  
  <p>SO: pushing my values to the atts array in the form_html function would be my solution. But honestly I don't know how-</p>
  
  <p>Thank you in advance!</p>