| # Largest Contentful Paint change in Chrome 116 to better handle animated content. |
| |
| Starting around Chrome 116, we're making two changes to the way that LCP handles |
| animated images and videos. In both cases, Chrome will count the time that the |
| first full frame is presented as the timestamp for the candidate. |
| |
| # Videos |
| |
| Videos have previously been ignored for LCP, unless they have a poster image. |
| With this change, a video element can become an LCP candidate, exactly like an |
| image. If it is used as a candidate, then the associated timestamp will be the |
| time that the first video frame is presented on screen. |
| |
| # Animated images |
| |
| Animated images (animated GIFs and PNGs) were previously not considered as LCP |
| candidates until they were fully loaded. For large files, this could be long |
| after the video has been playing on screen. This change counts the time that the |
| first frame of the animation is displayed, if the image becomes an LCP |
| candidate. |
| |
| ## How does this affect a site's metrics? |
| |
| Pages with large auto-playing videos should start seeing that video used as the |
| LCP element. LCP scores may improve or regress on those pages, depending on what |
| element is currently being chosen as LCP. |
| |
| Pages with large animated images will likely see LCP scores improve, as the |
| image will be reported with an earlier timestamp than before. |
| |
| Note for now, this only affects UKM (and so CrUX) reporting of LCP and does not |
| affect PerformanceObserver observations as measured in JavaScript. |
| |
| ## When were users affected? |
| |
| This change was launched to Chrome users starting on roughly 2023-08-22, to be |
| rolled out to existing Chrome 116+ installs over a 14 day period. |
