Circonian's LibNotification which I am taking care of is using a local copy of the KEYBOARD_NOTIFICATION_ICONS, GAMEPAD_NOTIFICATION_ICONS and DATA_TYPE_TO_TEMPLATE tables in notifications_keyboard.lua and notifications_gamepad.lua.
This means whenever I don't have time to update it (like it happened with Homestead), other addons will start to throw errors in case a new notification type has been added.
It would be good if these 3 tables could get added as properties on the NOTIFICATIONS and GAMEPAD_NOTIFICATIONS table so I can access them in the lib.
Or if you want to go the extra mile you could also look into adding a simple way to register custom notification types to the base game.
Does your addon work? [y/n] n
There is a typo in there.