Custom widget doesn't open in wp-admin

I created new widget position using this code:

<?php
if ( dynamic_sidebar('footer') ) :
else : ?>
<?php endif; ?>

and I registered it in functions.php:

if (function_exists('register_sidebar')){
			register_sidebar( array(
			'name' => 'Footer Menu',
			'id' => 'footer',
			'description'   => 'Footer menu',
			'before_widget' => '',
			'after_widget' => '',
			'before_title' => '',
			'after_title' => ''
));

    }

But when i’m going to Widgets area in admin – the new widget name displays correctly just under the default sidebar but when clicking on the little arrow it opens at the bottom of the page (where the Version of WP displays(!)), in all browsers, am I missing anything, why it’s behaving so weird?