I would like to build a dashboard and then be able to clone it with a different name of course.
Then I could modify only a few tiles in it and use it as a WAN dashboard only.
Like my Security dashboard on the LAN only I can Arm/Disarm and monitor all my security devices.
On the WAN version, I do not want Arm/Disarm available.
You can already do this. Select and Copy the JSON file in the advanced tab of the existing dashboard. Create your new dashboard and go into advanced tab again. Paste the JSON file there and click save layout JSON.
I posted this in another thread somewhere but I will add it here as well. Since copying and pasting the JSON works, it doesn't seem like too much of a leap to have the concept of "publishing" a dashboard from a master.
When I have a dashboard the way I want it, I turn off all the editing capabilities and lock my container dashboard and all the sub dashboards. As we all know, the instant you think things are just right some issue crops up and you need to adjust something. In my scenario, the master dashboards would always remain editable, while the published dashboards would not.