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diff --git a/devtools/client/netmonitor/test/browser_net_statistics-edge-case.js b/devtools/client/netmonitor/test/browser_net_statistics-edge-case.js
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+++ b/devtools/client/netmonitor/test/browser_net_statistics-edge-case.js
@@ -0,0 +1,112 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/**
+ * Tests if the statistics panel displays correctly for a page containing
+ * requests which have been known to create issues in the past for this Panel:
+ * - cached image (http-on-image-cache-response) requests in the content process
+ * - long polling requests remaining open for a long time
+ */
+
+add_task(async function () {
+  // We start the netmonitor on a basic page to avoid opening the panel on
+  // an incomplete polling request.
+  const { monitor } = await initNetMonitor(SIMPLE_URL, {
+    enableCache: true,
+  });
+
+  // The navigation should lead to 3 requests (html + image + long polling).
+  // Additionally we will have a 4th request to call unblock(), so there are 4
+  // requests in total.
+  // However we need to make sure that unblock() is only called once the long
+  // polling request has been started, so we wait for network events in 2 sets:
+  // - first the 3 initial requests, with only 2 completing
+  // - then the unblock request, bundled with the completion of the long polling
+  let onNetworkEvents = waitForNetworkEvents(monitor, 3, {
+    expectedPayloadReady: 2,
+    expectedEventTimings: 2,
+  });
+
+  // Here we explicitly do not await on navigateTo.
+  // The netmonitor will not emit "reloaded" if there are pending requests,
+  // so if the long polling request already started, we will never receive the
+  // event. Waiting for the network events should be sufficient here.
+  const onNavigationCompleted = navigateTo(STATISTICS_EDGE_CASE_URL);
+
+  info("Wait for the 3 first network events (initial)");
+  await onNetworkEvents;
+
+  // Prepare to wait for the second set of network events.
+  onNetworkEvents = waitForNetworkEvents(monitor, 1, {
+    expectedPayloadReady: 2,
+    expectedEventTimings: 2,
+  });
+
+  // Calling unblock() should allow for the polling request to be displayed and
+  // to complete, so we can consistently expect 2 events and 2 timings.
+  info("Call unblock()");
+  await SpecialPowers.spawn(gBrowser.selectedBrowser, [], () =>
+    content.wrappedJSObject.unblock()
+  );
+
+  info("Wait for polling and unblock (initial)");
+  await onNetworkEvents;
+
+  info("Wait for the navigation to complete");
+  await onNavigationCompleted;
+
+  // Opening the statistics panel will trigger a reload, expect the same requests
+  // again, we use the same pattern to wait for network events.
+  onNetworkEvents = waitForNetworkEvents(monitor, 3, {
+    expectedPayloadReady: 2,
+    expectedEventTimings: 2,
+  });
+
+  info("Open the statistics panel");
+  const panel = monitor.panelWin;
+  const { document, store, windowRequire, connector } = panel;
+  const Actions = windowRequire("devtools/client/netmonitor/src/actions/index");
+  store.dispatch(Actions.openStatistics(connector, true));
+
+  await waitFor(
+    () => !!document.querySelector(".statistics-panel"),
+    "The statistics panel is displayed"
+  );
+
+  await waitFor(
+    () =>
+      document.querySelectorAll(
+        ".table-chart-container:not([placeholder=true])"
+      ).length == 2,
+    "Two real table charts appear to be rendered correctly."
+  );
+
+  info("Close statistics panel");
+  store.dispatch(Actions.openStatistics(connector, false));
+
+  await waitFor(
+    () => !!document.querySelector(".monitor-panel"),
+    "The regular netmonitor panel is displayed"
+  );
+  info("Wait for the 3 first network events (after opening statistics panel)");
+  await onNetworkEvents;
+
+  onNetworkEvents = waitForNetworkEvents(monitor, 1, {
+    expectedPayloadReady: 2,
+    expectedEventTimings: 2,
+  });
+
+  info("Call unblock()");
+  await SpecialPowers.spawn(gBrowser.selectedBrowser, [], () =>
+    content.wrappedJSObject.unblock()
+  );
+
+  // We need to cleanly wait for all events to be finished, otherwise the UI
+  // will throw many unhandled promise rejections.
+  info("Wait for polling and unblock (after opening statistics panel)");
+  await onNetworkEvents;
+
+  await teardown(monitor);
+});