The bug

When running a scan in my network, the backend somehow finds a device on 192.168.2.6 which has the same MAC address as my router at 192.168.2.1. This causes an issue in the frontend in the "each_key" method from svelte:

Uncaught Error: https://svelte.dev/e/each_key_duplicate
    Immutable 44
    async* https://<domain>/device/new/:79
    promise callback* https://<domain>/device/new/:78
MXnx6da-.js:1:1838
    Immutable 43
    InterpretGeneratorResume self-hosted:1312
    AsyncFunctionNext self-hosted:780
    (Async: async)
    In Immutable
    InterpretGeneratorResume self-hosted:1312
    AsyncFunctionNext self-hosted:780
    (Async: async)
    <anonymous> https://<domain>/device/new/:79
    (Async: promise callback)
    <anonymous> https://<domain>/device/new/:78

In the frontend it just looks like the scan is loading forever.

I don't know why nmap finds a device on this IP address, in my router (FritzBox) it shows a vpn device there like this:
MyFRITZ!⁠App (Google Pixel 9) | VPN | 192.168.2.6 |   | VPN-Verbindung (IPSec)
This shows up as offline in the router though.

This causes the duplicate MAC address in the response from the backend (i guess) where device 0 and device 4 have the same mac address while having different IP adresses.

The OS that UpSnap is running on

Ubuntu 24.04.3 LTS (Noble Numbat) x86_64 (running with docker)

Version of UpSnap

5.2.8

Your docker-compose.yml content

services:
  upsnap:
    container_name: upsnap
    image: ghcr.io/seriousm4x/upsnap:5
    network_mode: host
    restart: unless-stopped
    privileged: true
    cap_add:
      - NET_RAW
    volumes:
      - ./data:/app/pb_data
    environment:
      - TZ=Europe/Berlin
      - UPSNAP_HTTP_LISTEN=0.0.0.0:8090
      - UPSNAP_INTERVAL=*/10 * * * * * 
      - UPSNAP_SCAN_RANGE=192.168.2.0/24 
      - UPSNAP_SCAN_TIMEOUT=200ms 
      - UPSNAP_PING_PRIVILEGED=true
    dns:
      - 192.168.2.1
      - 192.168.2.75

Reproduction steps

Probably hard to reproduce, might be router related. But as soon as there are duplicate MAC addresses in the network, this error occurs

Additional information

No response