$ sudo apt install curl
Others Linux Distribution also need to install "curl" package..
$ git clone https://github.com/yomun/gnome-backup-tools
$ cd gnome-backup-tools
$ mv backup-tools@yahoo.com ~/.local/share/gnome-shell/extensions
After 'Backup', you will get 3 files (e.g: gnome_shell_extensions_id.txt / gnome_shell_extensions_conf.txt)
These files will help you retrieve your GNOME Shell Extensions
Copyright © 2017-2020 Jason Mun (jasonmun@yahoo.com)
Released under the terms of the GNU General Public License, version 3