According to Fresh install of Ubuntu 22.04, LXD via snap, containers cannot reach the internet - #6 by tomp
sudo iptables -I DOCKER-USER -i lxdbr0 -j ACCEPT
sudo iptables -I DOCKER-USER -o lxdbr0 -j ACCEPT
The connectivity issue is solved.
According to Fresh install of Ubuntu 22.04, LXD via snap, containers cannot reach the internet - #6 by tomp
sudo iptables -I DOCKER-USER -i lxdbr0 -j ACCEPT
sudo iptables -I DOCKER-USER -o lxdbr0 -j ACCEPT
The connectivity issue is solved.