He himself asked - he himself found the answer in 10 minutes. To activate the plugin, you need to register not in main.inc.php but in config.inc.php somewhere on line 85 you will find this:
$config['plugins'] = array(
'autologin',
'archive',
'zip download',
);
In this array, add a line with the name of the plugin.
You won't figure it out yourself - no one will help you.
In simple words, in new versions of main.inc.php this is config.inc.php