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<!DOCTYPE html>
<html>
<body>
<style>
:root {
margin: 0px;
}
#spacer {
height: 100vh;
width: 100px;
}
#top_box {
width: 100px;
height: 60vh;
background-color: blue;
}
#middle_box {
width: 100px;
height: 60vh;
scroll-initial-target: nearest;
background-color: purple;
}
#bottom_box {
width: 100px;
height: 60vh;
background-color: yellow;
}
#fragment_target {
width: 100px;
height: 100px;
background-color: red;
}
</style>
<div id="top_box"></div>
<div id="middle_box"></div>
<div id="bottom_box"></div>
<div id="spacer"></div>
<div id="fragment_target">Target</div>
<script>
function stashResult(key, results) {
fetch(`/css/css-scroll-snap-2/scroll-initial-target/stash.py?key=${key}`, {
method: "POST",
body: JSON.stringify(results)
}).then(() => {
window.close();
});
}
function record() {
let scroll_position = "UNKNOWN";
// Expect page is scrolled all the way down as the text is at the bottom of
// the page.
const expected_scroll_top = document.scrollingElement.scrollHeight -
document.scrollingElement.clientHeight;
const scroll_start_target_top = top_box.getBoundingClientRect().height;
if (document.scrollingElement.scrollTop == scroll_start_target_top) {
scroll_position = "AT_SCROLL_START_TARGET";
} else if (document.scrollingElement.scrollTop == expected_scroll_top) {
scroll_position = "AT_TEXT_FRAGMENT";
}
const result = {
scroll_position: scroll_position
};
let key = (new URL(document.location)).searchParams.get("key");
stashResult(key, result);
}
window.onload = () => {
window.requestAnimationFrame(function () {
window.requestAnimationFrame(record);
})
}
</script>
</body>
</html>