Joomla! 5 ARTdev No Admin Plugin
One of the first things we should do when we put a Joomla site into production is hide access to the administrator . Nobody should access the /administrator folder of your website , neither curious, nor robots nor of course hackers. It is necessary to hide that folder for safety and also for a bit of modesty.
More info at https://artigot.dev/en/joomla/extensions/artdev-no-admin-plugin-for-joomla-eng