Not all templates have this behavior, but a lot of them, for example: Alcatel Timetra TiMOS by SNMP, Linux by SNMP, Mikrotik by SNMP, Windows by SNMP

Steps to reproduce:

1. Go to Data collection -> Templates
2. Select template 'Alcatel Timetra TiMOS by SNMP', template form dialog is opened
3. Click on Clone

Result:
For 7.0 all fields and tabs are cleared.

For 7.4 and master - nothing happens.

Expected:
Dialog form should change header from Temlpate to New template, fields and tabs should remain filled-in and only two buttons should remain: Add and Cancel, like it is on some other templated, for example 'AIX by Zabbix agent'