Very nice. I always pass at least 2 pieces of info in params: the locale and the timezone of the client; there is no better way to pass them.

The params can be either an object or a function returning an object. The second way is the best as used in the article. because during the LV session you could change any of your stored value so they would need to be re-evaluated in run-time, this is why it need to be a function.

Note that when the live view is mounted via a live_redirect (vs initial full page render), the element node passed to the params function will not have the full subtree, so node.querySelector("div[data-state-restore='true']") will return null and the restore data won’t be available in the connect params.