A Mozilla developer revealed one of the hidden techniques used by Firefox 57 aka Quantum, to improve page load times.
Mozilla has already mentioned a number of architectural changes to Firefox Quantum, which seem to have yielded improvements in speed and performance.
But Firefox 57 has another secret that it uses to achieve faster page load: it delays scripts from monitoring domains, such as www.google-analytics.com.
This technique was developed by the engineer of Mozilla Honza Bambas, who calls it “Tailing”. It works by delaying tracking and tracking scripts by opening a page, offering better load times.
The feature is not intended to improve it privacys, although it is based on data from Firefox's privacy protection feature Tracking Protection.
Cutting or to say better, the delay of these scrips simply prevents them from loading, and does not completely disable them.
So we can say that the best performance in loading a page is achieved by changing the browser's priority in site and site tracking requests.
“Requests remain pending while there are other requests from the page still loading and only for about 6 seconds. The delay only applies to scripts added dynamically or as async. Tracking images are always delayed. But it is legal according to all HTML specifications, and it is assumed that well-constructed spaces will not be affected in the functional", says Bambas.
This technique seems to work well, although in some cases it shows a blank page for a few seconds instead of gradually loading the page. Bambas refers to the Google page, Page-Hiding Snippet which uses as an example where this can happen.
However, as he points out “his intention tailing is to help with performance by delaying something that is not supposed to be visible. "
Firefox in addition to all of the above, also advances the project which will show all HTTP pages as insecure.
Currently it displays warnings on HTTP pages that manage login or financial data.
