I just finished a basic copy widget plugin for users who don’t have file system access to their kirby installation:
A copy/clone feature would ideally be added to the core panel dropdowns for pages and files, but until then someone might find this useful.
Hello Sweden! Is mogelbrod what I think it is? That green thing that grows? 
Anyway, interesting! 
Cloning seems hard to do, especially with many and large files. Timeouts and other funny things that could happend. 
Sure is! 
Yeah, execution time and memory limits can be problematic. It should
work fine for most page hierarchies though. The next release might add size
checking, possibly along with the option to exclude assets.