mail/gui.lua

if minetest.get_modpath("unified_inventory") then
	mail.receive_mail_message = mail.receive_mail_message ..
		" or use the mail button in the inventory"
	mail.read_later_message = mail.read_later_message ..
		" or by using the mail button in the inventory"

	unified_inventory.register_button("mail", {
			type = "image",
			image = "mail_button.png",
			tooltip = "Mail",
			action = function(player)
				mail.show_mail_menu(player:get_player_name())
			end
		})
end