After upgrading Syncthing Discovery Server from 1.23.4 to 1.29.3 on Debian, the service stopped starting with the error:
stdiscosrv: error: unknown flag -c, did you mean one of "-h", "-d", "-v"?
If I roll back stdiscosrv to 1.23.4 without changing anything else, everything works, no errors. I didn’t find anything about flag -c in the documentation. What could be the problem?