The copy functionality seems to work fine in this dialog:

as I can paste what I copied in other applications, such as Safari.
But after I navigate to the parent folder where I want to create the folder, and choose "New Folder", I get presented with this dialog:

where the paste functionality doesn't seem to work.
Yet I can use paste from similar dialogs in other applications (such as Safari).
If possible I'd like to be able to paste what I just copied in the previous step.
Hopefully this isn't a limitation of whatever framework MakeMKV uses.