This is my Kali Linux xfce4-genmon-plugin script to show multiple VPN/tuntap ip address usually for exercise lab setup

xfce4-panel-genmon-multiple-vpnip.sh

#!/bin/sh

interfaces="$(ip tuntap show | cut -d : -f1)"  # Get all VPN tuntap interfaces
TOOLTIP=$(ss -s | head -n 3 | grep -Ev "^$")
output=""
ip_to_copy=""

for interface in $interfaces; do
    ip="$(ip a s "${interface}" 2>/dev/null | grep -o -P '(?<=inet )[0-9]{1,3}(\.[0-9]{1,3}){3}')"

    if [ "${ip}" != "" ]; then
        output="${output} ${interface}: ${ip}"
        
        # Priority Logic: Overwrite if tun0, otherwise only set if empty
        if [ "${interface}" = "tun0" ]; then
            ip_to_copy="${ip}"
        elif [ "${ip_to_copy}" = "" ]; then
            ip_to_copy="${ip}"
        fi
    fi
done

if [ "${output}" != "" ]; then
    printf "<icon>network-vpn-symbolic</icon><txt>${output}</txt>"
    
    # Check for xclip and ensure we actually have an IP to copy
    if command -v xclip >/dev/null 2>&1 && [ "${ip_to_copy}" != "" ]; then
        # Using %s in printf is safer for variable injection
        printf "<tool>VPN IP ${ip_to_copy} (click to copy)\n\n${TOOLTIP}</tool>"
        printf "<txtclick>sh -c 'printf \"%%s\" \"%s\" | xclip -selection clipboard'</txtclick>" "${ip_to_copy}"
    else
        printf "<tool>${TOOLTIP}</tool>"
    fi
else
    printf "<txt></txt>"
fi

How to use on your fresh installed xfce4 kali linux machine

1. Grab this script and save to your preferred path (usually genmon script is at /usr/share/kali-themes/)
2. Add execute permission to the script
   chmod+x /path/to/xfce4-panel-genmon-multiple-vpnip.sh
3. Open xfce4 panel preferences then go to "Items" tab and find Generic Monitor (kali linux is having this by default if not found add manually)

4. Select Generic Monitor then click hamburger icon right to the remove button and it will open Generic Monitor Configuration window

5. Copy this saved script path and you can also configure how often this script is updated then click Save

6. It will loaded when any VPN/tuntap interface is available