FreeBSD packages didn't install mytop in versions before 10.3 and I was using mytop as a standalone package for the last 10+ years without any issues. Right after the upgrade from MariaDB 10.1 to 10.3 (and to bundled mytop) it doesn't work anymore. The problem is I have dedicated user account "mytop" specified in ~/.mytop and some other settings in ~/.my.cnf where password for another user account is stored too. MariaDB's version of mytop reads settings from ~/.my.cnf and uses them (different password) for mytop instead of settings from ~/.mytop so mytop cannot connect to database and settings cannot be overridden on commandline too.

I found that MariaDB's version implemented reading of ~/.my.cnf few years ago but it does not work as it should.

from manpage:
mytop will first read the [client] and [mytop] sections from your my.cnf
files. After that it will read the ("~/.mytop") file from your home
directory (if present). These are read before any of your command-line
arguments are processed, so your command-line arguments will override
directives in the config file.

I am not a Perl programmer but I tried to fix it and it works for me now (see attached patch).
I moved around the code for reading ~/.my.cnf and the way ~/.mytop is processed. Now all 3 kinds of configuration parameters are in ARGV and processed in correct order:
1) ~/.my.cnf (actually "my_print_defaults client mytop")
2) ~/.mytop
3) command line options

The later overrides value of earlier options.
Now everything works for me as before the upgrade.