The current minepacks file says 1.7-1.13. This plugin worked up until 1.16.4 where the plugin no longer works. Please update this plugin as it no longer works and this is quite important for people using this plugin including me as many people have valuable items stored in this plugin as it extends your inventory with a backpack. https://www.spigotmc.org/resources/minepacks-backpack-plugin-mc-1-7-1-16.19286/history