How to export Custom Button?

Hi all,
I use ManageIQ-fine2.
I want copy a custom button from MIQ A to MIQ B
The button used service-dialog and automate-script, I exported form Web UI.
I didn’t find the export custom-button from UI, so I create button manually on MIQB.
How to export Custom Button?

At the moment I think you’d have to do that via rake script. This used to work, albeit on the downstream version, although I haven’t tried it recently: