Common.js

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

/* Fix media negative margin bug for wide galleries */
$('.gallerybox audio').each(function(i, obj) {
	if ($(this).parent().css('margin-top') < '15px')
		$(this).parent().css('margin', '15px auto');
});

/* Default Special:ReplaceText to not announce edits */
$(function() {
	if (mw.config.get('wgCanonicalSpecialPageName') === 'ReplaceText')
		$('input[id="doAnnounce"]').prop('checked', false);
});

/* Default Special:UserMerge to user deletion */
$(function() {
	if (mw.config.get('wgCanonicalSpecialPageName') === 'UserMerge') {
		$('input[name="wpnewuser"]').val('Anonymous');
		$('input[name="wpdelete"]').prop('checked', true);
	}
});

/* Remove mobile title tags on desktop main page */
$(function() {
	if (mw.config.get('wgTitle') === 'Main Page') {
		$('div[id^="mf-"]').each(function(i, obj) {
			$(this).removeAttr('title');
		});
	}
});

/* Add subpages toolbox link on user pages */
$(function() {
	var title = mw.config.get('wgTitle');
	if (mw.config.get('wgCanonicalNamespace') === 'User' && !title.includes('/')) {
		var subpagesLink = '/Special:PrefixIndex/User:' + title + '/';
		mediaWiki.util.addPortletLink('p-tb', subpagesLink, 'User subpages', 't-subpages', 'Subpages of this page');
	}
});

/* Clean up the file extension for new uploads */
$(function() {
	if (mw.config.get('wgCanonicalSpecialPageName') === 'Upload' && !$('#wpForReUpload').length && !$('.warning').length)
		$('input[name=wpUpload]').click(function() {
			var file = $('#wpDestFile').val();
			if (file.includes('.')) {
				var fileName = file.substr(0, file.lastIndexOf('.'));
				var fileExt = file.split('.').pop().toLowerCase();
				if (fileExt == 'jpeg') fileExt = 'jpg';
				$('#wpDestFile').val(fileName + '.' + fileExt);
			}
		});
});

/* SocialProfile: Point social talk tabs to user talk */
$(function() {
	var namespace = mw.config.get('wgCanonicalNamespace');
	if (namespace === 'UserProfile' || namespace === 'UserWiki') {
		var talkTab;
		if (mw.config.get('skin') == 'nimbus') {
			talkTab = $('a[title="Discussion about the content page"]');
			talkTab.removeClass('tab-new');
		} else {
			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