What's rollout for in Tools?

[pyungdooj131661]

don't know what it is.....

I know what it is in Crxde ->> component - properties -> layout - rollout..

but I've never heard of this one.

what is it for and how to activate it?

In all pages , it is disabled.

[smacdonald2008]

See this doc - it talks about Rollout: 

https://docs.adobe.com/docs/en/cq/5-6-1/administering/tools.html