netbird + bridge

auto wt10
iface wt10 inet manual

auto vmbr10
iface vmbr10 inet manual
# IP-Transit Bridge
  mtu 1500
  bridge_ports none
  bridge_stp off
  bridge_fd 0
  post-up echo "1" > /proc/sys/net/ipv4/conf/vmbr10/forwarding
  post-up echo "1" > /proc/sys/net/ipv6/conf/all/forwarding
  pre-down echo "0" > /proc/sys/net/ipv6/conf/all/forwarding
  pre-down echo "0" > /proc/sys/net/ipv4/conf/vmbr10/forwarding
# Create a line for each IPAPI "Adresses" entry AND replace "<GATEWAY>" and "<CIDR>" using the advanced infromation of the subnet/info-button menu!
  post-up ip addr add <GATEWAY>/<CIDR>  dev vmbr10
# Create a line for each IPAPI "Adresses" entry and replace "<Subnet>" accordingly with its content! (Use copy button.) - required for local communication.
  post-up ip route add <Subnet> dev vmbr10 table 10
  post-up ip -4 rule add pref 10 from <Subnet> table 10 # Example for IPv4 ONLY!
  post-up ip -6 rule add pref 10 from <Subnet> table 10 # Example for IPv6 ONLY!
# Cleanup
  post-down sh -c 'while ip -4 rule del pref 10 2>/dev/null; do :; done'
  post-down sh -c 'while ip -6 rule del pref 10 2>/dev/null; do :; done'