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diff --git a/testing/web-platform/tests/soft-navigation-heuristics/softnav-before-lcp-paint.tentative.html b/testing/web-platform/tests/soft-navigation-heuristics/softnav-before-lcp-paint.tentative.html
new file mode 100644
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+++ b/testing/web-platform/tests/soft-navigation-heuristics/softnav-before-lcp-paint.tentative.html
@@ -0,0 +1,52 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+<meta charset="utf-8">
+<title>Detect simple soft navigation.</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/resources/testdriver.js"></script>
+<script src="/resources/testdriver-vendor.js"></script>
+<script src="resources/soft-navigation-helper.js"></script>
+<link rel="stylesheet" type="text/css" href="/fonts/ahem.css" />
+</head>
+<body>
+  <main id=main>
+    <div>
+      <a id=link><img src="/images/lcp-256x256.png"></a>
+    </div>
+  </main>
+  <script>
+    const link = document.getElementById("link");
+    testSoftNavigation({
+      addContent: async () => {
+        // Add an LCP element, large enough to trigger the Soft Navigation
+        // heuristics.
+        const p = addTextParagraphToMain("Lorem Ipsum", /*element_timing=*/"lcp");
+        p.id = "first_lcp";
+        // Once the first element is fully painted.
+        const observer = new PerformanceObserver(list => {
+          // Add a larger element to be the new LCP.
+          window.lcp_observer_promise = new Promise(resolve => {
+            (new PerformanceObserver(resolve)).observe({type: "element"});
+          });
+          const p2 = addTextParagraphToMain("LOREM IPSUMER", "real_lcp");
+          p2.id = "real_lcp";
+          observer.disconnect();
+        });
+        observer.observe({type: "element", buffered: true});
+      },
+      link: link,
+      validate: async () => {
+        await window.lcp_observer_promise;
+        const lcps = await getLcpEntries();
+        assert_greater_than_equal(lcps.length, 3, "Got at least 3 LCP entries");
+        assert_equals(lcps[lcps.length - 2].id, "first_lcp", "Got the first LCP");
+        assert_equals(lcps[lcps.length - 1].id, "real_lcp", "Got the real LCP");
+      },
+      test: "Test that an image LCP followed by 2 smaller soft navigation LCPs"
+        + " properly queues both LCP entries, even when the soft navigation"
+        + " is detected in between them."});
+  </script>
+</body>
+</html>