The objectactions was introduced after the objectdata domain in order to be more precise regarding the actions the user can perform.
It is disabled by default.
The domain "objectactions" is there to replace the domain "objectdata" only when the question is about a future action on the object.
When the domain "objectactions" is not activated then the system uses "objectdata" to answer the future questions.
As soon as it is activated then it is used for future questions and "objectdata" for saving.
In this domain, the new security rules available are :
create: can a new instance of this object be created ?
delete: can an instance of this object be deleted ?
order: can the instances of this object be ordered ?
multiupdate: si the bulk update function available ?
datavaluespicker: is it possible to pick some content to past on new instance or during multi-update ?
damimport: is it possible to bulk import via damimport ?
massimport: is it possible to bulk import directly in the object ?