Largest Contentful Paint Bug Fixes in M98

Bug Fixes in Chrome 98

In Chrome 98, a bug fix was made to the Chrome implementation. Previously, we would wait for one visual update at a time and record the paint times of all pending text nodes upon receiving the timestamp for the visual update. This could cause certain text nodes that had just been detected to be considered displayed even though they're not. Instead, we keep track of the objects which are painted on each animation frame and set their timestamps to the visual update corresponding to that animation frame. This is already how it works for image objects, so this change only impacts text paint times, making them more accurate. Source code for this change.

How does this affect a site's metrics?

A website whose LCP is text may see their LCP values increase due to the more accurate paint times being used.

When were users affected?

Chrome 98 is currently scheduled to be released the week of February 1, 2022.