Same for me...  blank on clean install  /una/page/messenger  using .13.   i do see :

info: connection from ip = ::ffff:74.103.xxx.xxx, id = ea41bbff-fe6b-4fee-8a29-4

47073ec4a83 in the console so the jot server and the messenger app are talking to one another if that helps at all. 

PS.  windows server IIS 8