How to encapsulate an existing package

Hello,

I am reviewing and cleaning existing custom code for a specific project and I'd like to encapsulate the existing packages in order to better understand the current dependencies.

But, while the "encapsulated" flag is available during SE21 package creation, I can't seem to find any place where I can change this property once the package is created. The only way I can see it is in the Package Hierarchy tab and it is read-only.

So how can I flag an exiting package as encapsulated?

Thanks in advance,

Nuno