Currently if the ajax call to get language pairs fails, "create new translation" button does nothing and this is in the console:
ext.cx.source.selector.js:46 Uncaught TypeError: Cannot read property 'length' of undefinedext.cx.source.selector.js:46 getAutonymsext.cx.source.selector.js:802 CXSourceSelector.renderext.cx.source.selector.js:77 (anonymous function)load.php?debug=true&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150217T02…:3300 (anonymous function)load.php?debug=true&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150217T02…:3143 jQuery.Callbacks.fireload.php?debug=true&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150217T02…:3255 jQuery.Callbacks.self.fireWithload.php?debug=true&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150217T02…:9309 doneload.php?debug=true&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150217T02…:9713 jQuery.ajaxTransport.send.callbackXMLHttpRequest.send (async)load.php?debug=true&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150217T02…:9659 jQuery.ajaxTransport.sendload.php?debug=true&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150217T02…:9210 jQuery.extend.ajaxload.php?debug=true&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150217T02…:9356 jQuery.each.jQuery.(anonymous function)ext.cx.source.selector.js:123 CXSourceSelector.getLanguagePairsext.cx.source.selector.js:76 CXSourceSelector.initext.cx.source.selector.js:34 CXSourceSelectorext.cx.source.selector.js:923 (anonymous function)load.php?debug=true&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150217T02…:384 jQuery.extend.eachload.php?debug=true&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150217T02…:136 jQuery.fn.jQuery.eachext.cx.source.selector.js:917 $.fn.cxSourceSelectorext.cx.dashboard.js:71 CXDashboard.listenext.cx.dashboard.js:30 CXDashboard.initext.cx.dashboard.js:24 CXDashboardext.cx.dashboard.js:80 (anonymous function)load.php?debug=true&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150217T02…:384 jQuery.extend.eachload.php?debug=true&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150217T02…:136 jQuery.fn.jQuery.eachext.cx.dashboard.js:75 $.fn.cxDashboardext.cx.dashboard.js:95 (anonymous function)load.php?debug=true&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150217T02…:3143 jQuery.Callbacks.fireload.php?debug=true&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150217T02…:3189 jQuery.Callbacks.self.addload.php?debug=true&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150217T02…:3423 jQuery.fn.readyload.php?debug=true&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150217T02…:2863 jQuery.fn.initload.php?debug=true&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=20150217T02…:73 jQueryext.cx.dashboard.js:94 (anonymous function)ext.cx.dashboard.js:97 (anonymous function)