Thanks for looking at it.
I replaced all ‘localhost’ to ‘127.0.0.1’ in all 3 .toml-files and restarted systemctl services. Still the same: trying to access the web-interface from another machine in the same network leads to ‘error parsing service config: error from DNS TXT record lookup: lookup _grpc_config.localhost on 192.168.2.1:53: read udp 192.168.2.108:59834->192.168.2.1:53: i/o timeout (code: 14)’ (see above). Tried with Firefox, and Safari on a third machine. Also another port instead of 8080.
Accessing ‘192.168.2.108:8080’ results in the error message above, in the browser address bar the ‘url’ changes to ‘192.168.2.108:8080/#/’