ACF Flexible Content layout collapse button

admin.js

function close_flexible_content(){
  $('.layout').attr('data-toggle', 'closed');
  $('.acf-input-table').css('display', 'none');
}
function open_flexible_content(){
  $('.layout').attr('data-toggle', 'open');
  $('.acf-input-table').css('display', 'table');
}
close_flexible_content();
$('.field_type-flexible_content').prepend('<a class="toggle_flexible_content button button-small" style="float: right; margin-top: -8px;" href="#">Toggle Layout Boxes</a>')
$('body').on('click', '.toggle_flexible_content', function(event){
  event.preventDefault();
  $this = $(this);
  if( $this.data('toggle') == 'open' ){
    close_flexible_content();
    $this.data('toggle', '');
  } else {
    open_flexible_content(); 
    $this.data('toggle', 'open');
  }
});