Please see the below screenshot. HTML5 to open CLient will get partial functionality.
I am aware of "Deploy OVF" at least will not be avaible on VC management console.
Log in Flash, right click the Data centre, or Cluster, or Hosts and VMS ICon, Deploy OVF aill be provided.
Log in HTML5, Deploy OVF only available on the host.
I think of it might be lost server useful functionality as VMware remind. VSphere CLient (HTML5) - partial functionality.
Yes, the HTML5 client embedded into vCenter 6.5 is not as fully featured as the one in 6.7. That's just life in software development. You can also deploy the standalone Fling and connect it to your vCenter environment which will give you more features.