A bug was introduced in Chromium 140 that caused the presentation time for some web page text to be reported earlier than it should have been. More specifically, when the presentation time was received for any text element, that timestamp was used for all painted text elements whose presentation time had not yet been set. This could cause text painted in quick succession of other text to have a presentation timestamp that too early, typically about one animation frame vsync interval, but potentially more in some cases. The bug impacted CrUX data, web-exposed LCP entries, and ElementTiming entries.
The bug was reported and fixed in Chromium 143, which was released to Stable in December 2025.
As a result of this issue, LCP may have erroneously appeared to improve between Chromium 140 and 142, inclusively. This only affected sites whose LCP element is text, and only in cases where the LCP element was painted soon after having painted other text elements, in another animation frame. The impact for such sites is expected to typically be on the order of dozens of milliseconds, but some variation is expected.
