How do i copy objects from one mission to another?

[MadTommy]

As the title says.

How do i select a group of objects, copy them and paste them into another mission?

Or merge two missions.

I'm sure this is possible, I've even done it myself ages ago.. just can't figure it out

The lack of documentation is really beginning to piss me off. Nothing is obvious or explained in this ******* mission editor.