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diff --git a/layout/reftests/scrolling/fractional-scroll-area-invalidation.html b/layout/reftests/scrolling/fractional-scroll-area-invalidation.html
new file mode 100644
index 0000000000..2b20f160cd
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+++ b/layout/reftests/scrolling/fractional-scroll-area-invalidation.html
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+<!DOCTYPE html>
+<html lang="en" reftest-async-scroll>
+<meta charset="utf-8">
+<title>Make sure the scrolled layer is not invalidated when you scroll all the way to the bottom</title>
+
+<style>
+
+body {
+  margin: 0;
+}
+
+.scrollbox {
+  margin: 50px;
+  width: 200px;
+  height: 200px;
+  overflow: auto;
+}
+
+.scrolled-contents {
+  height: 150.2px;
+  padding-top: 150px;
+}
+
+.reftest-no-paint {
+  margin: 0 20px;
+  border: 1px solid blue;
+  height: 25px;
+}
+
+</style>
+
+<body>
+
+<div class="scrollbox"
+     reftest-displayport-x="0" reftest-displayport-y="0"
+     reftest-displayport-w="200" reftest-displayport-h="200"
+     reftest-async-scroll-x="0" reftest-async-scroll-y="0">
+  <div class="scrolled-contents">
+    <div class="reftest-no-paint">
+      <!-- This element has the magic "reftest-no-paint" class which
+           constitutes the actual test here. -->
+    </div>
+  </div>
+</div>
+
+<script>
+
+var scrollbox = document.querySelector(".scrollbox");
+scrollbox.scrollTop = 2;
+scrollbox.scrollTop = 1;
+scrollbox.scrollTop = 0;
+
+function doTest() {
+  scrollbox.scrollTop = 999;
+  document.documentElement.removeAttribute("class");
+}
+document.addEventListener("MozReftestInvalidate", doTest);
+
+</script>