Favorites
Your tracked courses are stored in localStorage under favorites as an array of course IDs.
Export
Export creates a file named favorites.json with your IDs so you can back up or move to another browser.
Import
Import accepts either { "favorites": [1,2,3] } or a raw array like [1,2,3]. Invalid IDs are ignored.
Cart
Adding to cart updates localStorage.cart as [{ id, qty }].