After installing the plugin, the admin mail functionality will be restored to the way it was before version 4.9.
It may be required for sites without email access, or for testing purposes, i.e. using localhost, or if a new admin isn’t receiving an e-mail at his new address (the new admin email address cannot be active before it is confirmed).
Usage
Once activated, you can change the admin email by going to your site’s Dashboard -> “Settings” -> “Admin Email”.