Implement speculative prerendering (Speculation Rules)

[swissspidy]

Feature Description

The WordPress core performance team has recently launched the Speculation Rules feature plugin, which leverages the Speculation Rules API to enable dynamically prefetching/prerendering URLs based on user interaction.

See https://developer.chrome.com/docs/web-platform/prerender-pages for an explainer blog post.

This made me wonder how we could implement this API in Web Stories as well.

Some possibilities:

• In the Web Stories dashboard or the "All Stories" page:
  • Preload the editor when hovering over the story edit link
  • Maybe even preload the editor when hovering over the link to create a new story (if auto-drafts are not an issue)
  • Preload the story permalink when hovering over the link to view the story
• On the frontend
  • Support preloading the archive page or individual stories upon hovering

Implementation-wise:

• Leverage the Speculation Rules plugin if it is active
• If the plugin is not active:
  • Either add a new SpeculativePrerendering service.
  • Alternatively, add a new HasPrerendering interface so every relevant service can indicate preloading/prerendering rules for it.

A dedicated service is probably easiest, no need to overcomplicate things.

Alternatives Considered

Additional Context