At https://www.mediawiki.org/wiki/Special:NewMessages I'm getting this error message in webconsole:
"Exception thrown by ext.math.editbutton.enabler" load.php:150 "TypeError: mw.toolbar is undefined" TypeError: mw.toolbar is undefined Stack trace: @https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z line 4 > eval:2:2316 @https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z line 4 > eval:2:2235 runScript@https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z:161:128 execute/</checkCssHandles@https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z:161:613 execute@https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z:162:392 handlePending@https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z:159:664 runScript@https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z:161:140 execute/</checkCssHandles@https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z:161:613 execute/</cssHandle/<@https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z:161:743 jQuery.Callbacks/fire@https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z:45:106 jQuery.Callbacks/self.fireWith@https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z:46:431 jQuery.Callbacks/self.fire@https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z:46:474 addEmbeddedCSS@https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z:156:502 execute@https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z:162:199 mw.loader</<.implement@https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z:168:858 @https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z line 4 > eval:38:951 .globalEval/<@https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z:4:666 .globalEval@https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z:4:632 mw.loader</<.work@https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z:164:718 request@https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z:162:903 mw.loader</<.load@https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150107T194503Z:170:449 @https://www.mediawiki.org/wiki/Special:NewMessages:571:1
It doesn't seem to be a problem on any other pages that I can find.