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diff --git a/testing/web-platform/tests/css/css-scroll-anchoring/opt-out.html b/testing/web-platform/tests/css/css-scroll-anchoring/opt-out.html
new file mode 100644
index 0000000000..12d46c13f9
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+++ b/testing/web-platform/tests/css/css-scroll-anchoring/opt-out.html
@@ -0,0 +1,74 @@
+<!DOCTYPE html>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<style>
+
+body { height: 2000px; overflow-anchor: none; }
+#scroller { overflow: scroll; width: 500px; height: 300px; }
+.anchor {
+  position:relative; height: 100px; width: 150px;
+  background-color: #afa; border: 1px solid gray;
+}
+#forceScrolling { height: 500px; background-color: #fcc; }
+
+</style>
+<div id="outerChanger"></div>
+<div id="outerAnchor" class="anchor"></div>
+<div id="scroller">
+  <div id="innerChanger"></div>
+  <div id="innerAnchor" class="anchor"></div>
+  <div id="forceScrolling"></div>
+</div>
+<script>
+
+// Tests that scroll anchoring can be disabled per-scroller with the
+// overflow-anchor property.
+
+var divScroller = document.querySelector("#scroller");
+var docScroller = document.scrollingElement;
+var innerChanger = document.querySelector("#innerChanger");
+var outerChanger = document.querySelector("#outerChanger");
+
+function setup() {
+  divScroller.scrollTop = 100;
+  docScroller.scrollTop = 100;
+  innerChanger.style.height = "200px";
+  outerChanger.style.height = "150px";
+}
+
+function reset() {
+  document.body.style.overflowAnchor = "";
+  divScroller.style.overflowAnchor = "";
+  divScroller.scrollTop = 0;
+  docScroller.scrollTop = 0;
+  innerChanger.style.height = "";
+  outerChanger.style.height = "";
+}
+
+test(() => {
+  setup();
+
+  assert_equals(divScroller.scrollTop, 300,
+      "Scroll anchoring should apply to #scroller.");
+
+  assert_equals(docScroller.scrollTop, 100,
+      "Scroll anchoring should not apply to the document scroller.");
+
+  reset();
+}, "Disabled on document, enabled on div.");
+
+test(() => {
+  document.body.style.overflowAnchor = "auto";
+  divScroller.style.overflowAnchor = "none";
+  setup();
+
+  assert_equals(divScroller.scrollTop, 100,
+      "Scroll anchoring should not apply to #scroller.");
+
+  assert_equals(docScroller.scrollTop, 250,
+      "Scroll anchoring should apply to the document scroller.");
+
+  reset();
+}, "Enabled on document, disabled on div.");
+
+</script>