@Evg-R said in Can't open Nodebb with URL from config.json:
And docs says I should access http://forum.example.com just after installation
No hosts or dns setup are mentioned!
Because this is so basic it is assume. It is assumed that you would have bought a domain, set it up, made the entry. This isn't a level of thing that would be explained in a software installation document.
All documents, ever written, that mention a URL mean "a working URL that points to the correct IP record for the machine in question." The documents don't mention installing your OS or making your networking work either, but obviously that also is required. DNS/Hostname is just the same, part of the basic networking.