Remove Specific Classes from a Gravity Form

remove-specific-classes-from-gravity-form.php

<?php
// Remove gf_hidden and gf_invisible classes from all fields
add_filter( 'gform_pre_render', 'remove_display_hidden_classes' );
add_filter( 'gform_pre_validation', 'remove_display_hidden_classes' );
add_filter( 'gform_pre_submission_filter', 'remove_display_hidden_classes' );
add_filter( 'gform_admin_pre_render', 'remove_display_hidden_classes' );

function remove_display_hidden_classes( $form ) {
  foreach ( $form['fields'] as &$field ) {
    $classes = explode( ' ', $field->cssClass ); // 'class1 class2' : array( 'class1', 'class2' )
    $classes = array_diff( $classes, array( 'gf_hidden', 'gf_invisible' ) );
    $field->cssClass = implode( ' ', $classes ); 
  }
  return $form;
}