Where is the DDNS configuration in GL-MT300A's 3.20 firmware?

After updating my GL-MT300A to firmware 3.20 I couldn’t find the option to configure a DDNS (I would like to configure opendns-o-matic).

Could anyone tell me where this configuration could be done?

 

Regards,

 

if it is not in luci, you may need to install luci-app-ddns