Output buffering allows admin screens to make redirects later on.
Include any classes we need within admin.
Include admin files conditionally.
Handle redirects to setup/welcome page after install and updates.
For setup wizard, transient must be present, the user must have access rights, and we must ignore the network/bulk plugin updaters.
Prevent any user who cannot 'edit_posts' (subscribers, customers etc) from accessing admin.
Preview email template.
admin_footer_text( string $footer_text )
Change the admin footer text on WooCommerce admin pages.