I was looking for a tea timer countdown but quickly realised I might as well use a countdown script for this. I based my script on the linked script but added a customizable notification at the end
$ nano ~/bin/countdown#!/bin/bash<br></br># v2 - 2019-05-01<br></br>secs=$1<br></br>msg=${2:-$1 seconds passed.}<br></br>while [ $secs -gt 0 ]; do<br></br> echo -ne "$secs\033[0K\r"<br></br> sleep 1<br></br> : $((secs--))<br></br>done<br></br>notify-send 'Countdown Finished' "$msg"<br></br><br></br>$ chmod +x ~/bin/countdown<br></br>$ countdown 180 "Tea is ready."