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The following walk through works on Debian 9, 10, and 11.
sudo apt update sudo apt install snapd sudo snap install core sudo snap refresh core
sudo apt remove --purge certbot sudo rm /usr/local/bin/certbot-auto
sudo snap install --classic certbot sudo ln -s /snap/bin/certbot /usr/bin/certbot
sudo certbot renew --dry-run
systemctl list-timers
certbot
certbot certificates
certbot --expand -d example.com,www.example.com,click.example.com certbot certonly --webroot --agree-tos -w /srv/www/letsencrypt/ --expand -d example.com,www.example.com,click.example.com
certbot revoke --cert-path /etc/letsencrypt/live/example.com/cert.pem
certbot delete --cert-name www.example.com
certbot delete
$ sudo crontab -e 35 3 * * 6 certbot renew && /etc/init.d/apache2 restart