*Contact emails*
[email protected]

*Specification*
https://github.com/w3c/largest-contentful-paint/pull/154

*Summary*
Changes the LCP algorithm to emit candidates based on the largest painted
image instead of the largest pending-but-not-yet-painted image. This might
cause more intermediate candidates to be emitted to the performance
timeline.

In each animation frame, after presentation, the LCP algorithm will emit a
new candidate (at most one) to the performance timeline if a new largest
text or image was painted in that frame. But Chromium also tracks the
"largest pending image" (the largest image still loading) and uses that
image's size to determine if the new candidate is the largest. This means a
slow-loading large image can prevent the emission of intermediate LCP
candidates, and developers often find such candidates useful for
understanding the loading progression. This behavior came up during Interop
2025 as a difference with other engines, and there was agreement to align
on emitting at most one candidate per frame based on the set of painted
image/text elements for that frame.

*Blink component*
Blink>PerformanceAPIs
<https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3EPerformanceAPIs%22>

*Web Feature ID*
largest-contentful-paint
<https://webstatus.dev/features/largest-contentful-paint>

*Risks*


*Interoperability and Compatibility*
*No information provided*

*Gecko*: No signal

*WebKit*: No signal

*Web developers*: No signals

*Other signals*:

*WebView application risks*

Does this intent deprecate or change behavior of existing APIs, such that
it has potentially high risk for Android WebView-based applications?
*No information provided*


*Debuggability*
*No information provided*

*Will this feature be supported on all six Blink platforms (Windows, Mac,
Linux, ChromeOS, Android, and Android WebView)?*
No

*Is this feature fully tested by web-platform-tests
<https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md>?*
Yes
https://github.com/web-platform-tests/wpt/blob/master/largest-contentful-paint/performance-entry-sequence.html



*Tracking bug*
https://issues.chromium.org/issues/482261053

*Estimated milestones*
Shipping on desktop 146
Shipping on Android 146
Shipping on WebView 146

*Link to entry on the Chrome Platform Status*
https://chromestatus.com/feature/5167930847395840

This intent message was generated by Chrome Platform Status
<https://chromestatus.com/>.

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