Version 8.1 Hangs up
PermalinkFailed to load resource: the server responded with a status of 504 (Gateway Time-out)
install:1 Uncaught ReferenceError: registrar_frameset is not defined
at eval (eval at <anonymous> (jquery.js:2), <anonymous>:1:2)
at eval (<anonymous>)
at jquery.js:2
at Function.globalEval (jquery.js:2)
at m.fn.init.domManip (jquery.js:4)
at m.fn.init.append (jquery.js:4)
at showFailure (install:58)
at Object.<anonymous> (install:243)
at j (jquery.js:2)
at Object.fireWith [as rejectWith] (jquery.js:2)
You could also look at your server error log and php error log. But I would try the above first. Unless you are very familiar with the server stuff, the browser developer console is a lot easier to get to grips with.