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diff --git a/devtools/client/inspector/test/browser_inspector_remove-iframe-during-load.js b/devtools/client/inspector/test/browser_inspector_remove-iframe-during-load.js
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+++ b/devtools/client/inspector/test/browser_inspector_remove-iframe-during-load.js
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+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+"use strict";
+
+// Testing that the inspector doesn't go blank when navigating to a page that
+// deletes an iframe while loading.
+
+const TEST_URL = URL_ROOT + "doc_inspector_remove-iframe-during-load.html";
+
+add_task(async function () {
+  const { inspector, tab } = await openInspectorForURL("about:blank");
+  await selectNode("body", inspector);
+
+  // Before we start navigating, attach a listener on the reloaded event.
+  const onInspectorReloaded = inspector.once("reloaded");
+
+  // Note: here we don't want to use the `navigateTo` helper from shared-head.js
+  // because we want to modify the page as early as possible after the
+  // navigation, ideally before the inspector has fully initialized.
+  // See next comments.
+  const browser = tab.linkedBrowser;
+  const onBrowserLoaded = BrowserTestUtils.browserLoaded(browser);
+  BrowserTestUtils.loadURIString(browser, TEST_URL);
+  await onBrowserLoaded;
+
+  // We do not want to wait for the inspector to be fully ready before testing
+  // so we load TEST_URL and just wait for the content window to be done loading
+  await SpecialPowers.spawn(browser, [], async function () {
+    await content.wrappedJSObject.readyPromise;
+  });
+
+  // The content doc contains a script that creates iframes and deletes them
+  // immediately after. It does this before the load event, after
+  // DOMContentLoaded and after load. This is what used to make the inspector go
+  // blank when navigating to that page.
+  // At this stage, there should be no iframes in the page anymore.
+  ok(
+    !(await contentPageHasNode(browser, "iframe")),
+    "Iframes added by the content page should have been removed"
+  );
+
+  // Create/remove an extra one now, after the load event.
+  info("Creating and removing an iframe.");
+  await SpecialPowers.spawn(browser, [], async function () {
+    const iframe = content.document.createElement("iframe");
+    content.document.body.appendChild(iframe);
+    iframe.remove();
+  });
+
+  ok(
+    !(await contentPageHasNode(browser, "iframe")),
+    "The after-load iframe should have been removed."
+  );
+
+  // Assert that the markup-view is displayed and works
+  ok(!(await contentPageHasNode(browser, "iframe")), "Iframe has been removed");
+
+  const expectedText = await SpecialPowers.spawn(
+    browser,
+    [],
+    async function () {
+      return content.document.querySelector("#yay").textContent;
+    }
+  );
+  is(expectedText, "load", "Load event fired.");
+
+  info("Wait for the inspector to be properly reloaded");
+  await onInspectorReloaded;
+
+  // Smoke test to check that the inspector can still select nodes and hasn't
+  // gone blank.
+  await selectNode("#yay", inspector);
+});
+
+function contentPageHasNode(browser, selector) {
+  return SpecialPowers.spawn(
+    browser,
+    [selector],
+    async function (selectorChild) {
+      return !!content.document.querySelector(selectorChild);
+    }
+  );
+}