Alex Goes Fuhrmann and Pomsky have described the process to pin folders to the files icon on the Ubuntu dock in 18.04 (How do I pin my favorite folders in Ubuntu dock like in Windows?). I had this working in 18.04, but it no longer applies in 20.04.
In 20.04, there are 2 files related to nautilus in /usr/share/applications: naultilus-autorun-software.desktop and org.gnome.Nautilus.desktop. The latter is very similar to nautilus.desktop.
So I followed the same procedure (copy org.gnome.Nautilus.desktop to ~/.local/share/applications, edit the "Actions=" line and add "[Desktop-Action ...]" sections). Now, while the new locations are listed under the files icon, only the first (--new-window) does anything.
What is wrong, or missing?