Exception encountered, of type "Error"
[ZgX9d-9cyt7dAV6Y-mgIpwAAABQ] /index.php?title=Special:UserLogin&returnto=Workshops&returntoquery=diff%3Dnext%26oldid%3D1783 Error from line 663 of /www/htdocs/brucon/2015/includes/exception/MWExceptionHandler.php: Class 'FormatJson' not found
Backtrace:
#0 /www/htdocs/brucon/2015/includes/exception/MWExceptionHandler.php(242): MWExceptionHandler::logError()
#1 /www/htdocs/brucon/2015/includes/AutoLoader.php(81): MWExceptionHandler::handleError()
#2 /www/htdocs/brucon/2015/includes/AutoLoader.php(81): require()
#3 [internal function]: AutoLoader::autoload()
#4 /www/htdocs/brucon/2015/includes/Xml.php(668): spl_autoload_call()
#5 /www/htdocs/brucon/2015/includes/Xml.php(684): Xml::encodeJsVar()
#6 /www/htdocs/brucon/2015/includes/OutputPage.php(3071): Xml::encodeJsCall()
#7 /www/htdocs/brucon/2015/includes/OutputPage.php(3130): OutputPage->getScriptsForBottomQueue()
#8 /www/htdocs/brucon/2015/includes/skins/Skin.php(596): OutputPage->getBottomScripts()
#9 /www/htdocs/brucon/2015/includes/skins/SkinTemplate.php(458): Skin->bottomScripts()
#10 /www/htdocs/brucon/2015/includes/skins/SkinTemplate.php(246): SkinTemplate->prepareQuickTemplate()
#11 /www/htdocs/brucon/2015/includes/OutputPage.php(2335): SkinTemplate->outputPage()
#12 /www/htdocs/brucon/2015/includes/MediaWiki.php(743): OutputPage->output()
#13 /www/htdocs/brucon/2015/includes/MediaWiki.php(509): MediaWiki->main()
#14 /www/htdocs/brucon/2015/index.php(43): MediaWiki->run()
#15 {main}