User blog comment:Rappy 4187/Technical Update: February 5, 2013/@comment-13301-20130208174528

Since the fix for tabber and slider is getting too slow, admins can edit MediaWiki:Monobook,js and add the following code to fix it meanwhile:

function fixTabber { if ($('div.tabber', '#mw-content-text').length > 0 && typeof window.tabberObj == 'undefined') { importScriptURI(mw.config.get('wgExtensionsPath') + '/3rdparty/tabber/tabber.js?' + mw.config.get('wgStyleVersion')); } } $(fixTabber); function fixSlider { if ($('#wikiaPhotoGallery-slider-body-0').length > 0 && typeof window.WikiaPhotoGallerySlider == 'undefined') { importStylesheetURI(mw.config.get('wgExtensionsPath') + '/wikia/WikiaPhotoGallery/css/WikiaPhotoGallery.slidertag.css?' + mw.config.get('wgStyleVersion')); $.getScript(mw.config.get('wgExtensionsPath') + '/wikia/WikiaPhotoGallery/js/WikiaPhotoGallery.slider.js?' + mw.config.get('wgStyleVersion'), function {			for (var sid = 0; document.getElementById('wikiaPhotoGallery-slider-body-'+sid.toString) !== null; sid++) {				WikiaPhotoGallerySlider.init(sid);			}		}); } } $(fixSlider);

It shouldn't cause any issue once Wikia fixes the problem (it checks whether the missing functions exist or not before loading them), but after fixed you should remove that code.