/etc/my.cnf.d/server.cnf is messed up after saving the settings in mysql_manager

After saving the configs (changing bind-address) at the settings page in mysql_manager, mysql failed to restart, checked the contents of /etc/my.cnf.d/server.cnf and saw that the setting is like this

[server]
 = 3306

I had to add "port" to this line to start the mysql (mariadb 10.4.22) again:

[server]
port = 3306