<?php add_action ( 'edit_category_form_fields', 'extra_category_fields');
//add extra fields to category edit form callback function
function extra_category_fields( $tag ) {    //check for existing featured ID
    $t_id = $tag->term_id;
    $cat_meta = get_option( "category_$t_id");
?>
<label for="extra3"><?php _e('More field'); ?></label>
<?php $settings = array( 'textarea_name' => 'css[extra3]' ); wp_editor( $cat_meta['extra3'], 'css-extra3',$settings ); ?>
<?php
add_action ( 'edited_category', 'save_extra_category_fileds');
   // save extra category extra fields callback function
function save_extra_category_fileds( $term_id ) {
    if ( isset( $_POST['css'] ) ) {
        $t_id = $term_id;
        $cat_meta = get_option( "category_$t_id");
        $cat_keys = array_keys($_POST['css']);
            foreach ($cat_keys as $key){
            if (isset($_POST['css'][$key])){
                $cat_meta[$key] = $_POST['css'][$key];
            }
        }
        //save the option array
        update_option( "category_$t_id", $cat_meta );
    }
}
} ?>

<?php $cat_id = Category_ID;
$cat_data = get_option("category_$cat_id");
echo do_shortcode($cat_data['extra3']); ?>