RUM update: lux.js v308

24 May 2023 (UTC)

Pages that are prerendered are now flagged as such.
Pages that are restored from the back-forward cache (bfcache) can now be tracked by setting LUX.newBeaconOnPageShow = true. Read the documentation for more information on how this works.
Server timing metrics are now extracted from the main page response. Metrics must be configured in your SpeedCurve settings before they are collected.

The beacon will no longer be sent automatically if the page visibility is hidden. This can be overridden by setting LUX.trackHiddenPages = true.
All metrics on prerendered pages are now relative to activationStart.
Navigation timing values with a value of zero are now reported, rather than ignored.
The legacy domLoading metric is no longer collected.
The first paint event of any type will be considered for start render, rather than just first-paint events.

Timing values are now rounded down to the nearest unit to prevent values from being rounded into the future.