| <!DOCTYPE html> | |
| <div id="target" style="height: 100px; background-color: green;"></div> | |
| <script> | |
| const observer = new IntersectionObserver(records => { | |
| records.forEach(record => { | |
| if (record.isIntersecting) { | |
| window.top.postMessage(record.isIntersecting, "*"); | |
| } | |
| }); | |
| }, {}); | |
| observer.observe(target); | |
| window.addEventListener("load", () => { | |
| window.top.postMessage("ready", "*"); | |
| }); | |
| </script> |