Yeah, as a last resort that is a good suggestion. On a proper computer you could even use "save page as" and have it run the javascript so you can use all of the functionality (e.g., checking items off, or temporarily hiding when you're planning to get them in the next store) except that the syncing will fail until you get back home, which would be okay then.

It's a rare situation though, otherwise it would have been worth it to make a proper app that caches all data locally rather than a webpage