Websites and web apps continue to grow more complex, which is why Google is constantly working on new performance improvements for the Chrome browser. Now the company is trying a new experiment that could lead to faster load times.
Long ago, web browsers used to load the entire contents of a page at the same time — images, embedded plugins, you name it. Over time, browsers and websites started shifting to “lazy loading,” where some content isn’t loaded until it’s visible. For example, a site might not load a video halfway down the page until you scroll that far down.
Google Chrome has supported lazy load for most embedded objects, like videos and PDFs, since July 2020 (and many sites had their own hacks for it before then). To avoid breaking anything, Chrome only lazy-loads embedded content if the page specifically allows it. However, Google is now testing a new experiment that will lazy-load some embedded content automatically, without the page asking for it.
The new experiment, dubbed “LazyEmbeds,” is planned to start with 1% of people running the stable version of Chrome 104 (due for release on August 2). Embedded content that meets certain criteria (hosted from a third-party site, source matches a curated list, size of the frame, etc.) won’t load until it’s visible on the page, just like images and other embeds that have opted into lazy loading.
Google is hoping the feature could bring the performance and battery life benefits of lazy loading to even more pages, without breaking any sites in the process. The explainer document says, “it’s not uncommon for an embed to request and execute large amounts of script, which can have a surprising impact on the performance of the parent page – from resource contention to delaying interaction readiness.”
Google said in 2020 that lazy-loading YouTube videos on Chrome.com reduced load times on mobile by 10 seconds, and lazy-loading Instagram embeds saved more than 1MB of data usage. Those improvements would be great to see on more pages, but we’ll have to wait for the experiment’s results to see if it breaks any sites. If it works out, the feature should arrive in other Chromium-based web browsers, like Microsoft Edge, Brave, and Vivaldi.