Most of my VMs are in my local network, but I have one external server that I use Tailscale to access. The host running the main portracker container has Tailscale installed, and it can access the external server.
If I have Tailscale connected on the device I'm using to view the portracker frontend, the page loads immediately. If I disconnect from Tailscale though, it takes ~20 seconds to load. Once it loads, everything works fine. All the stats are visible for the external server, so it can clearly still communicate with it. The only change is that the client viewing the frontend can't access the external server