Common.js

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/* Any JavaScript here will be loaded for all users on every page load. */

/* Fix media wide gallery negative margin bug */
$('.gallerybox > div > .thumb > div:first-child').each(function(i, obj) {
	if ($(this).css('margin-top') == '-25px')
		$(this).css('margin', '15px auto');
});

/* SocialProfile: Point social talk tabs to user talk */
$(function() {
	var namespace = mw.config.get('wgCanonicalNamespace');
	if (namespace === 'UserProfile' || namespace === 'UserWiki') {
		if (mw.config.get('skin') == 'nimbus') {
			var talkTab = $('a[title="Discussion about the content page"]');
			talkTab.removeClass('tab-new');
		} else {
			var talkTab = $('#ca-talk a');
			$('#ca-talk').removeClass('new');
		}
		var talkUrl = talkTab.attr('href').replace('index.php?title=', '').replace(namespace, 'User').replace('&action=edit&redlink=1', '');
		var subIndex = talkUrl.indexOf('/', 1);
		if (subIndex > 0)
			talkUrl = talkUrl.substring(0, subIndex);
		talkTab.attr('href', talkUrl);
	}
});

MediaWiki:Common.js