Page B

Same document shape, different page, reached the same ordinary way.

If this mode prerenders, this page may have finished loading before you clicked. The diagnostics panel below tells you whether it did.

A placeholder standing where a real page would put its artwork.

The swap looks continuous, but under throttling the animation still waits for the slow destination.

Evidence lives in DevTools too. Open the Application panel, find Speculative loads under Background services, and the Speculations tab lists every URL this page tried to prepare, with its status.