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<!doctype html>
<meta charset="utf-8">
<title>Test textarea scroll restoration</title>
<link rel="help" href="https://html.spec.whatwg.org/#the-textarea-element-2">
<link rel="author" title="Emilio Cobos Álvarez" href="mailto:emilio@crisal.io">
<link rel="author" title="Mozilla" href="https://mozilla.com">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<div id="container">
<textarea id="textarea" rows=3>
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</textarea>
</div>
<script>
function frame() {
return new Promise(r => {
requestAnimationFrame(() => requestAnimationFrame(r));
});
}
let container = document.getElementById("container");
let textarea = document.getElementById("textarea");
async function test_restoration() {
textarea.scrollTop = 10000;
await frame();
let top = textarea.scrollTop;
assert_not_equals(top, 0, "Should've scrolled down");
container.style.display = "inline-block";
assert_equals(textarea.scrollTop, top, "Should've preserved the scroll position");
container.style.display = "";
}
promise_test(test_restoration);
promise_test(async function() {
textarea.focus();
await frame();
await test_restoration();
}, "after focus");
</script>
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