I'm running cockpit 137 on a fedora 25 server and when I go to the cockpit login page on port 9090, I get this: http://i.imgur.com/12ucNiY.png

The cockpit service becomes inactive after a few seconds when I restart it:

# systemctl status cockpit
● cockpit.service - Cockpit Web Service
   Loaded: loaded (/usr/lib/systemd/system/cockpit.service; static; vendor preset: disabled)
   Active: inactive (dead) since Wed 2017-05-31 11:39:35 CEST; 2min 11s ago
     Docs: man:cockpit-ws(8)
  Process: 25616 ExecStart=/usr/libexec/cockpit-ws (code=exited, status=0/SUCCESS)
  Process: 25613 ExecStartPre=/usr/sbin/remotectl certificate --ensure --user=root --group=cockpit-ws --selinux-type=etc_t (code=exited, status=0/SUCCESS)
 Main PID: 25616 (code=exited, status=0/SUCCESS)

May 31 11:38:05 systemd[1]: Starting Cockpit Web Service...
May 31 11:38:05 systemd[1]: Started Cockpit Web Service.
May 31 11:38:05 cockpit-ws[25616]: Using certificate: /etc/cockpit/ws-certs.d/~self-signed.cert