diff --git a/devtools/client/netmonitor/src/components/new-request/HTTPCustomRequestPanel.js b/devtools/client/netmonitor/src/components/new-request/HTTPCustomRequestPanel.js
index 1894f1be042d..4806d3d3e9d1 100644
--- a/devtools/client/netmonitor/src/components/new-request/HTTPCustomRequestPanel.js
+++ b/devtools/client/netmonitor/src/components/new-request/HTTPCustomRequestPanel.js
@@ -122,10 +122,12 @@ class HTTPCustomRequestPanel extends Component {
 
   async componentDidMount() {
     let { connector, request } = this.props;
-    const persistedCustomRequest = await asyncStorage.getItem(
-      "devtools.netmonitor.customRequest"
-    );
-    request = request || persistedCustomRequest;
+    if (!connector.currentTarget?.targetForm?.isPrivate) {
+      const persistedCustomRequest = await asyncStorage.getItem(
+        "devtools.netmonitor.customRequest"
+      );
+      request = request || persistedCustomRequest;
+    }
 
     if (!request) {
       this.setState({ _isStateDataReady: true });
@@ -191,7 +193,9 @@ class HTTPCustomRequestPanel extends Component {
   }
 
   componentWillUnmount() {
-    asyncStorage.setItem("devtools.netmonitor.customRequest", this.state);
+    if (!this.props.connector.currentTarget?.targetForm?.isPrivate) {
+      asyncStorage.setItem("devtools.netmonitor.customRequest", this.state);
+    }
   }
 
   handleChangeURL(event) {
diff --git a/devtools/client/netmonitor/test/browser_net_new_request_panel_persisted_content.js b/devtools/client/netmonitor/test/browser_net_new_request_panel_persisted_content.js
index 509bbc000041..51d37a2e4acf 100644
--- a/devtools/client/netmonitor/test/browser_net_new_request_panel_persisted_content.js
+++ b/devtools/client/netmonitor/test/browser_net_new_request_panel_persisted_content.js
@@ -9,30 +9,14 @@ const asyncStorage = require("resource://devtools/shared/async-storage.js");
  * Test if content is still persisted after the panel is closed
  */
 
-add_task(async function () {
-  // Turn true the pref
-  await pushPref("devtools.netmonitor.features.newEditAndResend", true);
-  // Reset the storage for the persisted custom request
-  await asyncStorage.removeItem("devtools.netmonitor.customRequest");
-
-  const { monitor } = await initNetMonitor(HTTPS_CUSTOM_GET_URL, {
-    requestCount: 1,
-  });
-  info("Starting test... ");
-
-  const { document, store, windowRequire } = monitor.panelWin;
-
-  // Action should be processed synchronously in tests.
-  const Actions = windowRequire("devtools/client/netmonitor/src/actions/index");
-  store.dispatch(Actions.batchEnable(false));
-
-  info("open the left panel");
-  let waitForPanels = waitForDOM(
+async function addCustomRequestTestContent(tab, monitor, document) {
+  info("Open the left panel");
+  const waitForPanels = waitForDOM(
     document,
     ".monitor-panel .network-action-bar"
   );
 
-  let HTTPCustomRequestButton = document.querySelector(
+  const HTTPCustomRequestButton = document.querySelector(
     "#netmonitor-toolbar-container .devtools-http-custom-request-icon"
   );
   HTTPCustomRequestButton.click();
@@ -59,91 +43,166 @@ add_task(async function () {
     "#http-custom-query .map-add-new-inputs .http-custom-input-name"
   );
   newParameterName.focus();
-  EventUtils.sendString("My-param");
+  EventUtils.sendString("My-param", monitor.panelWin);
 
   info("Adding new headers");
   const newHeaderName = document.querySelector(
     "#http-custom-headers .map-add-new-inputs .http-custom-input-name"
   );
   newHeaderName.focus();
-  EventUtils.sendString("My-header");
+  EventUtils.sendString("My-header", monitor.panelWin);
 
   const newHeaderValue = Array.from(
     document.querySelectorAll(
       "#http-custom-headers .http-custom-input .http-custom-input-value"
     )
-  ).pop();
+  ).at(-1);
   newHeaderValue.focus();
-  EventUtils.sendString("my-value");
+  EventUtils.sendString("my-value", monitor.panelWin);
 
   const postValue = document.querySelector("#http-custom-postdata-value");
   postValue.focus();
-  EventUtils.sendString("{'Name': 'Value'}");
+  EventUtils.sendString("{'Name': 'Value'}", monitor.panelWin);
 
-  // Close the panel
+  info("Close the panel");
   const closePanel = document.querySelector(
     ".network-action-bar .tabs-navigation .sidebar-toggle"
   );
   closePanel.click();
+}
 
-  // Open the panel again to see if the content is still there
-  waitForPanels = waitUntil(
+async function runTests(tab, monitor, document, isPrivate = false) {
+  info("Open the panel again to see if the content is still there");
+  const waitForPanels = waitFor(
     () =>
       document.querySelector(".http-custom-request-panel") &&
       document.querySelector("#http-custom-request-send-button").disabled ===
-        false
+        isPrivate
   );
 
-  HTTPCustomRequestButton = document.querySelector(
+  const HTTPCustomRequestButton = document.querySelector(
     "#netmonitor-toolbar-container .devtools-http-custom-request-icon"
   );
   HTTPCustomRequestButton.click();
   await waitForPanels;
 
-  is(
-    methodValue.value,
-    "POST",
-    "The content should still be there after the user close the panel and re-opened"
-  );
+  // Wait a few seconds to make sure all the fields have been updated
+  await wait(1500);
 
-  is(
-    url.value,
-    "https://www.example.com?My-param=",
-    "The url should still be there after the user close the panel and re-opened"
+  const customMethod = document.querySelector("#http-custom-method-value");
+  const customUrl = document.querySelector(".http-custom-url-value");
+  const customQuery = document.querySelectorAll(
+    "#http-custom-query .tabpanel-summary-container.http-custom-input textarea"
   );
+  const customHeaders = document.querySelectorAll(
+    "#http-custom-headers .tabpanel-summary-container.http-custom-input textarea"
+  );
+  const postDataValue = document.querySelector("#http-custom-postdata-value");
 
-  const [nameParam] = Array.from(
-    document.querySelectorAll(
-      "#http-custom-query .tabpanel-summary-container.http-custom-input textarea"
-    )
-  );
-  is(
-    nameParam.value,
-    "My-param",
-    "The Parameter name should still be there after the user close the panel and re-opened"
-  );
+  if (isPrivate) {
+    is(
+      customMethod.value,
+      "GET",
+      "The method should not be persisted after the user close the panel and re-opened in PBM"
+    );
 
-  const [name, value] = Array.from(
-    document.querySelectorAll(
-      "#http-custom-headers .tabpanel-summary-container.http-custom-input textarea"
-    )
-  );
-  is(
-    name.value,
-    "My-header",
-    "The header name should still be there after the user close the panel and re-opened"
-  );
-  is(
-    value.value,
-    "my-value",
-    "The header value should still be there after the user close the panel and re-opened"
-  );
+    is(
+      customUrl.value,
+      "",
+      "The url should not be there after the user close the panel and re-opened in PBM"
+    );
 
-  is(
-    postValue.value,
-    "{'Name': 'Value'}",
-    "The content should still be there after the user close the panel and re-opened"
-  );
+    is(
+      customQuery.length,
+      0,
+      "The Parameter should not be there after the user close the panel and re-opened in PBM"
+    );
 
+    is(
+      customHeaders.length,
+      0,
+      "There should be no custom headers after the user close the panel and re-opened in PBM"
+    );
+
+    is(
+      postDataValue.value,
+      "",
+      "The post data should still be reset after the user close the panel and re-opened in PBM"
+    );
+  } else {
+    is(
+      customMethod.value,
+      "POST",
+      "The method should be persisted after the user close the panel and re-opened"
+    );
+
+    is(
+      customUrl.value,
+      "https://www.example.com?My-param=",
+      "The url should still be there after the user close the panel and re-opened"
+    );
+
+    const [nameParam] = Array.from(customQuery);
+    is(
+      nameParam.value,
+      "My-param",
+      "The Parameter name should still be there after the user close the panel and re-opened"
+    );
+
+    const [name, value] = Array.from(customHeaders);
+    is(
+      name.value,
+      "My-header",
+      "The header name should still be there after the user close the panel and re-opened"
+    );
+    is(
+      value.value,
+      "my-value",
+      "The header value should still be there after the user close the panel and re-opened"
+    );
+
+    is(
+      postDataValue.value,
+      "{'Name': 'Value'}",
+      "The content should still be there after the user close the panel and re-opened"
+    );
+  }
+}
+
+add_task(async function testRequestPanelPersistedContent() {
+  // Turn true the pref
+  await pushPref("devtools.netmonitor.features.newEditAndResend", true);
+  // Reset the storage for the persisted custom request
+  await asyncStorage.removeItem("devtools.netmonitor.customRequest");
+
+  const { tab, monitor } = await initNetMonitor(HTTPS_CUSTOM_GET_URL, {
+    requestCount: 1,
+  });
+  const { document, store, windowRequire } = monitor.panelWin;
+  const Actions = windowRequire("devtools/client/netmonitor/src/actions/index");
+  store.dispatch(Actions.batchEnable(false));
+
+  info("Starting test... ");
+  info("Add initial custom request test content");
+  await addCustomRequestTestContent(tab, monitor, document);
+  await runTests(tab, monitor, document);
   await teardown(monitor);
 });
+
+add_task(async function testRequestPanelPersistedContentInPrivateWindow() {
+  await pushPref("devtools.netmonitor.features.newEditAndResend", true);
+  const { tab, monitor, privateWindow } = await initNetMonitor(
+    HTTPS_CUSTOM_GET_URL,
+    {
+      requestCount: 1,
+      openInPrivateWindow: true,
+    }
+  );
+  const { document, store, windowRequire } = monitor.panelWin;
+  const Actions = windowRequire("devtools/client/netmonitor/src/actions/index");
+  store.dispatch(Actions.batchEnable(false));
+
+  info("Starting test in private window... ");
+  await runTests(tab, monitor, document, true);
+  await teardown(monitor, privateWindow);
+});
diff --git a/devtools/client/netmonitor/test/head.js b/devtools/client/netmonitor/test/head.js
index b171b51715a2..258a8ba9f6cf 100644
--- a/devtools/client/netmonitor/test/head.js
+++ b/devtools/client/netmonitor/test/head.js
@@ -321,6 +321,7 @@ function initNetMonitor(
     expectedEventTimings,
     waitForLoad = true,
     enableCache = false,
+    openInPrivateWindow = false,
   }
 ) {
   info("Initializing a network monitor pane.");
@@ -341,7 +342,22 @@ function initNetMonitor(
       ],
     });
 
-    const tab = await addTab(url, { waitForLoad });
+    let tab = null;
+    let privateWindow = null;
+
+    if (openInPrivateWindow) {
+      privateWindow = await BrowserTestUtils.openNewBrowserWindow({
+        private: true,
+      });
+      ok(
+        PrivateBrowsingUtils.isContentWindowPrivate(privateWindow),
+        "window is private"
+      );
+      tab = BrowserTestUtils.addTab(privateWindow.gBrowser, url);
+    } else {
+      tab = await addTab(url, { waitForLoad });
+    }
+
     info("Net tab added successfully: " + url);
 
     const toolbox = await gDevTools.showToolboxForTab(tab, {
@@ -371,7 +387,7 @@ function initNetMonitor(
       await clearNetworkEvents(monitor);
     }
 
-    return { tab, monitor, toolbox };
+    return { tab, monitor, toolbox, privateWindow };
   })();
 }
 
@@ -408,7 +424,7 @@ async function clearNetworkEvents(monitor) {
   store.dispatch(Actions.clearRequests());
 }
 
-function teardown(monitor) {
+function teardown(monitor, privateWindow) {
   info("Destroying the specified network monitor.");
 
   return (async function () {
@@ -419,6 +435,12 @@ function teardown(monitor) {
 
     await monitor.toolbox.destroy();
     await removeTab(tab);
+
+    if (privateWindow) {
+      const closed = BrowserTestUtils.windowClosed(privateWindow);
+      privateWindow.BrowserCommands.tryToCloseWindow();
+      await closed;
+    }
   })();
 }