Service worker (optimized to increase page loading speeds) and the Performance Timing API which is included within all browsers to provide data that can then be used to measure performance across your site.
It supports both Level 1 and Level 2 specifications of the API and includes some additional information to help further enrich the data collected.

The main features of this plugin are as follows:

* Collection of the raw data provided by the browser like Page loading speeds, Event loading times, DOM loading and completion times, Domain lookup times, Transfer sizes etc.

* Additional Web Core Vitals information including more advanced metrics like TTFB, LCP, FCP, FID and CLS data. Refer to the documentation page for a full description on what these mean!

* Actions to monitor workflow response times up to millisecond accuracy (from frontend workflows) and the ability to set thresholds so you can see if any workflows are taken longer than normal to complete.

* The ability to utilise a service worker which will cache all images, fonts, css, links, pages etc to the browser increasing all page speed times, great for progressive web apps and to enable these resources for offline use.


NOTE ON THE SERVICE WORKER: Depending on the complexity and how large your app is, this may or may not show a noticeable speed increase. The service worker proactively controls the caching of all necessary resources and should load substantially faster when reloading your pages which is great for returning visitors. It means all that data, whether it be images, scripts or other things (including fonts and pages) are all available even when offline.

Try this plugin before you purchase it. It's not a solution for magically making all scores hit he green zone through Google Lighthouse. It may help the scores but there is too much going on with the way Bubble generally loads our pages that no plugin can totally alleviate.