I am experiencing this as well. I had changed the DNS servers to 1.1.1.1 and followed that whole deal. I uninstalled and reinstalled Five.M and nothing changed. I have looked through multiple Reddit forums, Five.M forums and google and found no fix for this concern. I am not the owner of the server, just a Mod.
Update: I am stupid and was using the wrong IP address to connect. But F8 drop downs still inop in client.