My IP: 10.78.16.20
I want to open an app at 10.78.16.30. Chrome tells me ERR_ADDRESS_UNREACHABLE.
Yet Safari can open it. ICMP, SSH works.
What gives?
Trying to search for an answer to this is painful between all the "check your network, check your modem, restart Chrome" useless answers.
If you are running macOS Sequoia, there's a good chance you need to enable Local Network access under System Settings -> Privacy & Security -> Local Network. Make sure that Google Chrome is turned on, as well as any other third-party browsers you use.
Normally, you get ask for this permission upon first launch of Google Chrome, but it's easy to hit the wrong key and dismiss it.
Check whether the target host allows incoming tcp/udp connections.
Also, because of the IP range you posted: If you are using a VPN, the client could be misconfigured. It could be that the VPN client is e.g. exposing a local SOCKS or HTTP/HTTPS proxy that Chrome ignores.