1) Boot to a live Focal USB
2) Enable -proposed pocket and add universe to the repo
3) Upgrade gnome-shell-extension-desktop-icons to 20.04.0-3~ubuntu20.04.3
4) Logout and login to restart gnome-shell
5) Use the touchscreen to double tap on "Home" and "Trash" icons, the respective directories can be opened all the time.
For gnome-shell- extension- desktop- icons on Focal:
1) Boot to a live Focal USB extension- desktop- icons to 20.04.0- 3~ubuntu20. 04.3
2) Enable -proposed pocket and add universe to the repo
3) Upgrade gnome-shell-
4) Logout and login to restart gnome-shell
5) Use the touchscreen to double tap on "Home" and "Trash" icons, the respective directories can be opened all the time.