Doesn't work as it should

[okalm]

Hi,

A tiny error prevent the script from working properly, it looks like echo -n isn't Posix enough although the manpage says otherwise if I get it right.
https://man.freebsd.org/cgi/man.cgi?query=echo&apropos=0&sektion=0&manpath=FreeBSD+13.2-RELEASE+and+Ports&arch=default&format=html

Just replacing it by printf does the job and the script works well now:

Thank you for this converted shell script mate, much appreciated :)