Enable desktop notifications trigger urgent flag for your Slack running in Linux via Dunst filters

dunst-slack.sh

#!/bin/sh -ex
# THIS SCRIPT ASSUMES YOU DON'T HAVE A CUSTOM DUNST SETUP IN ~/.config/dunst/dunstrc!!!!!!

# https://geekoverdose.wordpress.com/2019/08/01/i3-window-manager-selectively-make-any-notification-urgent-urgency-flag-to-highlight-the-workspace/

mkdir -p ~/bin

DUNST=~/bin/dunst-urgent-notification

cat >$DUNST <<BEGIN
#!/bin/sh
wmctrl -r \$1 -b add,demands_attention

BEGIN

chmod +x $DUNST

mkdir -p ~/.config/dunst

DUNSTRC=~/.config/dunst/dunstrc

zcat /usr/share/doc/dunst/dunstrc.gz > $DUNSTRC
cat >>$DUNSTRC <<BEGIN

[slack]
    appname = "Slack"
    summary = "*" 
    # this is the filter criterion applied to the message, see below
    # urgency = critical # those attributes could be used to set details of the message in the script called below
    # format = "" # could be used to alter the popup text, see below
    script = ~/bin/dunst-urgent-notification # this is the script that is called, see below

BEGIN

killall dunst; notify-send "Slack notifications now set up!"

wmctrl needs to be pre-installed before using this. also moving dunst-urgent-notification to ~/.config/dunst is more reasonable.

This has a bug where if you have an another window starting with "Slack..." that window is going to be marked as URGENT