MediaWiki:Common.js

// Reverse-sort Blogs
$(document).ready(function() {
    if (mw.config.get('wgCanonicalNamespace') === 'Category' && 
        mw.config.get('wgTitle') === 'Blog') {
        
        var $categoryList = $('#mw-pages');
        if ($categoryList.length) {
            var $items = $categoryList.find('li');
            $items.detach().sort(function(a, b) {
                return $(b).text().localeCompare($(a).text());
            });
            $categoryList.append($items).show();
        }
    }
});