You can't. OnDemand has a fixed list of plugins that Atlassian will allow you to buy and install. If it's not on that list, then you can't have it.
You can try asking Atlassian to add it to the list, but the list really does grow very slowly. No harm in asking.
You could hang on a while though - they are planning to implement a lot more flexibility on plugins quite soon, but I don't know exactly how much or when ("Summer" was the last implementation date I've seen mentioned)
I’m a designer on the Jira team. For a long time, I’ve fielded questions from other designers about how they should be using Jira Software with their design team. I’ve also heard feedback from other ...
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