Today, the LCP spec wording suggests that multiple LCP candidates would be emitted within a single Paint / rendering update, in cases where there are multiple new "largest" candidates in one paint operation but the overall largest isn't first.

The algorithm already has access to all image & text paint records, so we could easily just take the single largest instead.

See Context.

• Paint Timing Spec defines "mark paint timing" called from HTML "update the rendering"
• Per spec, we collect a set of ALL painted image/text nodes that paint.
• We create a callback in step 10 to flushPaintTimings. (This is optionally called synchronously, or in parallel after presentation time is available)
• flushPaintTimings calls "report largest contentful paint" with the list of image/text candidates.
• "report largest contentful paint", will iterate the list (in arbitrary order) and create entries.