By default, MediaWiki shows additional items in the footer such as the time of the last page modification, the privacy policy, etc.

You can remove these items by modifying the skins file of your MediaWiki. The default skin's file is skins/MonoBook.php.

Open the file with a text editor and find this section:

       // Generate additional footer links
?>
            <ul id="f-list">
<?php
        $footerlinks = array(
            'lastmod', 'viewcount', 'numberofwatchingusers', 'credits', 'copyright',
            'privacy', 'about', 'disclaimer', 'tagline',
        );

The items in the array represent the footer links in your MediaWiki. If you wish to remove a certain item from your footer, you should delete its entry from the array.

For example, if you wish to remove the Privacy policy link, you should delete the 'privacy' item from the array. Then open your MediaWiki in a browser and clean the page cache to see the change.