A commit has been accepted into GNOME to remove the desktop icons capability from Files.
Reasoning is that it removes lots of deprecated code and prevents future enhancements to Files (Nautilus).
There is a prototype gnome-shell extension that has been mooted - no idea if its going to be ready within the 18.04 LTS timescales.
Unfortunately for desktop environments such as Budgie Desktop that depends on key components like Files, we’ll lose the ability to have desktop icons - something Budgie users on the whole want.
Discussion - for the wider GNOME-Shell and Unity user communities what do you think? Is it better to request the Ubuntu Desktop Team to consider sticking with Files v3.26 that has desktop icons or keep with upstream GNOME and push for Files v3.28 that hasnt got this capability?