moderate viewport heuristic -- source

Four anchors registered as moderate-eagerness prefetch candidates via the <script type="speculationrules"> document rule above. Scroll until the gradient HERO card visually fills the viewport, stop and wait ~600ms; the heuristic picks the anchor with the largest size_in_viewport. Move the mouse off the page first to remove hover-triggered prefetches from the trigger column.

speculation rules supported --
candidates registered --
screen --
viewport --
pointer: coarse --
hover: hover --
UAData.mobile --
narrow (max-width: 600px) --
visibilityState --
scrollWidth / innerWidth --
scroll down
dummy-1.html
small sibling 1
dummy-2.html
small sibling 2
target.html
HERO — largest in-viewport anchor

This card is min-height: 70vh. When it visually fills the viewport it dominates by size_in_viewport. The heuristic picks this and prefetches target.html.

dummy-3.html
small sibling 3
end