How to enable desktop icons in Ubuntu 20.04
Undo what you did and revert to the default extension with following commands
gnome-extension disable desktop-icons@csoriano-local
rm -rf ~/.local/share/gnome-shell/extensions/desktop-icons@csoriano-local
gnome-extension enable desktop-icons@csoriano
Be very carefull with he second rm command: copy it here and paste it in the terminal. Sloppiness where a space is inserted on the wrong place could cause the command to delete other contents in your home folder.