Linux Headless Server: Not showing up in LAN Browser

[Pariah Zero]

I've got a Linux Headless server, and as the subject suggests, it's not showing up in the LAN browser.

• I have no problems if I use the "Connect to Address" dialog and input the Hostname, IPv4, or IPv6 address (and port)
• For both IPv4 and IPv6, the server is on a slightly different subnet/prefix
  • 192.168.1.0/24 || 2601:0000:0000:0000:\:/64 for most machines on my network
  • 192.168.2.0/24 || 2601:0000:0000:/64 for the Linux Headless server
• There is a firewall that blocks pretty much everything except UDP port 34197 and SSH.

Other than that, there's nothing special happening: There's no routing magick, no port remapping, and the two subnets have no problems routing to each other. Does Factorio simply not consider a different subnet part of the LAN?

Thanks.