Tricks

Get workspace dimensions

swaymsg -t get_outputs | jq -r '.[] | select(.focused) | (.current_mode.width | tostring) + "x" + (.current_mode.height | tostring)'

Tamefox - suspend Firefox when loses focus

#!/bin/sh
firefox=
swaymsg -m -t subscribe '["window"]' | \
        jq -r --unbuffered '.change +" "+  .container.app_id + " " + (.container.pid | tostring)' | \
        grep --line-buffered '^focus ' | \
        while read -r x app pid; do
                #echo "# x=$x app=$app pid=$pid" >&2
                if [ "$app" = 'firefox' ]; then
                        echo "CONT $pid" >&2
                        firefox=$pid
                        kill -CONT $pid
                        pkill -CONT -P $pid
                elif [ -n "$firefox" ]; then
                        echo "STOP $firefox" >&2
                        pkill -STOP -P $firefox
                        kill -STOP $firefox
                fi
        done

save it as $HOME/bin/tamefox and add this to your .config/sway/config:

exec [ -x $HOME/bin/tamefox ] && $HOME/bin/tamefox