two points
-localStorage works on the background.html page
-when content scripts access localStorage, they do so at the domain level of the url
-localStorage works on the background.html page
-when content scripts access localStorage, they do so at the domain level of the url
* localStorage also works from the popup (using the same storage as the background; that's how the tutorial was able to work).
* We're trying to get data working in the popup here, so how localStorage works in the contentscripts is irrelevant for solving this problem.