Importing .fzz file into another .fzz file

I designed two boards in two different files. But now I want to put them in a single board. So I want to import one of the boards into the other. How do I do this ? Please help.

The only way is to highlight all the parts (ctrl+a) and copy them (ctrl+c) and then in another sketch paste them (ctr+v). The only problem this creates is it only maintains the routing of the view you copy and paste. If you copy and paste the PCB layer it will look exactly as it did but the schematic and breadboard will lose all their routing and be nothing but ratsnests. This is fine if all you are doing is putting them on a single PCB for fabrication but a bit of a pain when you want all the views correct.

Thank you very much @sublimeartistry
I don’t care about the schematic and breadboard as I never use them.