This could perhaps be a much more stable alternative to my reverse SSH tunnels for keeping connections with various servers, especially desktops inside FM-NET and other machines inside other LANs.
The main downside is that Tailscale is not FOSS. So perhaps we should look for other solutions built on WireGuard, or perhaps learn to configure WireGuard directly.

• https://github.com/tailscale/tailscale
• https://tailscale.com/blog/how-tailscale-works/
• https://worlditguy.com/network/how-to-install-tailscale-on-windows-and-linux/