--- a/devtools/client/inspector/grids/test/browser_grids_number-of-css-grids-telemetry.js
+++ b/devtools/client/inspector/grids/test/browser_grids_number-of-css-grids-telemetry.js
@@ -32,17 +32,16 @@ add_task(async function() {
 
   info("Navigate to TEST_URI2");
 
   const onGridListUpdate = waitUntilState(
     store,
     state => state.grids.length == 1
   );
   await navigateTo(
-    inspector,
     "data:text/html;charset=utf-8," + encodeURIComponent(TEST_URI2)
   );
   await onGridListUpdate;
 
   checkResults();
 });
 
 function checkResults() {

--- a/devtools/client/inspector/grids/test/browser_grids_restored-after-reload.js
+++ b/devtools/client/inspector/grids/test/browser_grids_restored-after-reload.js
@@ -96,17 +96,17 @@ add_task(async function() {
   );
   const otherUri =
     "data:text/html;charset=utf-8," + encodeURIComponent(OTHER_URI);
   onStateRestored = highlighters.once("grid-state-restored");
   onGridListRestored = waitUntilState(
     store,
     state => state.grids.length == 1 && !state.grids[0].highlighted
   );
-  await navigateTo(inspector, otherUri);
+  await navigateTo(otherUri);
   ({ restored } = await onStateRestored);
   await onGridListRestored;
 
   info(
     "Check that the grid highlighter is hidden after navigating to a different page"
   );
   ok(!restored, "The highlighter state was not restored");
   ok(!highlighters.gridHighlighters.size, "CSS grid highlighter is hidden.");

--- a/devtools/client/inspector/markup/test/browser_markup_events_source_map.js
+++ b/devtools/client/inspector/markup/test/browser_markup_events_source_map.js
@@ -36,17 +36,17 @@ add_task(async function() {
     INITIAL_URL
   );
 
   // Ensure the source map service is operating.  This looks a bit
   // funny, but sourceMapURLService is a getter, and we don't need the
   // result.
   toolbox.sourceMapURLService;
 
-  await navigateTo(inspector, TEST_URL);
+  await navigateTo(TEST_URL);
 
   await inspector.markup.expandAll();
 
   for (const test of TEST_DATA) {
     await checkEventsForNode(test, inspector, testActor);
   }
 
   // Wait for promises to avoid leaks when running this as a single test.

--- a/devtools/client/inspector/rules/test/browser_rules_eyedropper.js
+++ b/devtools/client/inspector/rules/test/browser_rules_eyedropper.js
@@ -44,17 +44,17 @@ add_task(async function() {
   const url = "data:text/html;charset=utf-8," + encodeURIComponent(TEST_URI);
   await addTab(url);
 
   const { testActor, inspector, view, toolbox } = await openRuleView();
 
   await runTest(testActor, inspector, view, false);
 
   info("Reload the page to restore the initial state");
-  await navigateTo(inspector, url);
+  await navigateTo(url);
 
   info("Change toolbox host to WINDOW");
   await toolbox.switchHost("window");
 
   // Switching hosts is not correctly waiting when DevTools run in content frame
   // See Bug 1571421.
   await wait(1000);
 

--- a/devtools/client/inspector/rules/test/browser_rules_flexbox-highlighter-on-navigate.js
+++ b/devtools/client/inspector/rules/test/browser_rules_flexbox-highlighter-on-navigate.js
@@ -26,11 +26,11 @@ add_task(async function() {
   const flexboxToggle = container.querySelector(".ruleview-flex");
 
   info("Toggling ON the flexbox highlighter from the rule-view.");
   const onHighlighterShown = highlighters.once("flexbox-highlighter-shown");
   flexboxToggle.click();
   await onHighlighterShown;
   ok(highlighters.flexboxHighlighterShown, "Flexbox highlighter is shown.");
 
-  await navigateTo(inspector, TEST_URI_2);
+  await navigateTo(TEST_URI_2);
   ok(!highlighters.flexboxHighlighterShown, "Flexbox highlighter is hidden.");
 });

--- a/devtools/client/inspector/rules/test/browser_rules_flexbox-highlighter-restored-after-reload.js
+++ b/devtools/client/inspector/rules/test/browser_rules_flexbox-highlighter-restored-after-reload.js
@@ -56,13 +56,13 @@ add_task(async function() {
     "Check that the flexbox highlighter can be displayed after reloading the page"
   );
   ok(highlighters.flexboxHighlighterShown, "Flexbox highlighter is shown.");
 
   info("Navigate to another URL, and check that the highlighter is hidden");
   const otherUri =
     "data:text/html;charset=utf-8," + encodeURIComponent(OTHER_URI);
   onStateRestored = highlighters.once("flexbox-state-restored");
-  await navigateTo(inspector, otherUri);
+  await navigateTo(otherUri);
   ({ restored } = await onStateRestored);
   ok(!restored, "The highlighter state was not restored");
   ok(!highlighters.flexboxHighlighterShown, "Flexbox highlighter is hidden.");
 });

--- a/devtools/client/inspector/rules/test/browser_rules_grid-highlighter-on-navigate.js
+++ b/devtools/client/inspector/rules/test/browser_rules_grid-highlighter-on-navigate.js
@@ -30,11 +30,11 @@ add_task(async function() {
 
   info("Toggling ON the CSS grid highlighter from the rule-view.");
   const onHighlighterShown = highlighters.once("grid-highlighter-shown");
   gridToggle.click();
   await onHighlighterShown;
 
   is(highlighters.gridHighlighters.size, 1, "CSS grid highlighter is shown.");
 
-  await navigateTo(inspector, TEST_URI_2);
+  await navigateTo(TEST_URI_2);
   ok(!highlighters.gridHighlighters.size, "CSS grid highlighter is hidden.");
 });

--- a/devtools/client/inspector/rules/test/browser_rules_grid-highlighter-restored-after-reload.js
+++ b/devtools/client/inspector/rules/test/browser_rules_grid-highlighter-restored-after-reload.js
@@ -63,13 +63,13 @@ add_task(async function() {
     "Check that the grid highlighter can be displayed after reloading the page"
   );
   is(highlighters.gridHighlighters.size, 1, "CSS grid highlighter is shown.");
 
   info("Navigate to another URL, and check that the highlighter is hidden");
   const otherUri =
     "data:text/html;charset=utf-8," + encodeURIComponent(OTHER_URI);
   onStateRestored = highlighters.once("grid-state-restored");
-  await navigateTo(inspector, otherUri);
+  await navigateTo(otherUri);
   ({ restored } = await onStateRestored);
   ok(!restored, "The highlighter state was not restored");
   ok(!highlighters.gridHighlighters.size, "CSS grid highlighter is hidden.");
 });

--- a/devtools/client/inspector/rules/test/browser_rules_selector-highlighter-on-navigate.js
+++ b/devtools/client/inspector/rules/test/browser_rules_selector-highlighter-on-navigate.js
@@ -13,31 +13,31 @@ const TEST_URI = `
   </style>
   Test the selector highlighter
 `;
 
 const TEST_URI_2 = "data:text/html,<html><body>test</body></html>";
 
 add_task(async function() {
   await addTab("data:text/html;charset=utf-8," + encodeURIComponent(TEST_URI));
-  const { inspector, view } = await openRuleView();
+  const { view } = await openRuleView();
   const highlighters = view.highlighters;
 
   info("Clicking on a selector icon");
   const icon = await getRuleViewSelectorHighlighterIcon(view, "body, p, td");
 
   const onToggled = view.once("ruleview-selectorhighlighter-toggled");
   EventUtils.synthesizeMouseAtCenter(icon, {}, view.styleWindow);
   const isVisible = await onToggled;
 
   ok(
     highlighters.selectorHighlighterShown,
     "The selectorHighlighterShown is set."
   );
   ok(view.selectorHighlighter, "The selectorhighlighter instance was created");
   ok(isVisible, "The toggle event says the highlighter is visible");
 
-  await navigateTo(inspector, TEST_URI_2);
+  await navigateTo(TEST_URI_2);
   ok(
     !highlighters.selectorHighlighterShown,
     "The selectorHighlighterShown is unset."
   );
 });

--- a/devtools/client/inspector/test/browser_inspector_destroy-after-navigation.js
+++ b/devtools/client/inspector/test/browser_inspector_destroy-after-navigation.js
@@ -3,19 +3,19 @@
 "use strict";
 
 // Testing that closing the inspector after navigating to a page doesn't fail.
 
 const URL_1 = "data:text/plain;charset=UTF-8,abcde";
 const URL_2 = "data:text/plain;charset=UTF-8,12345";
 
 add_task(async function() {
-  const { inspector, toolbox } = await openInspectorForURL(URL_1);
+  const { toolbox } = await openInspectorForURL(URL_1);
 
-  await navigateTo(inspector, URL_2);
+  await navigateTo(URL_2);
 
   info("Destroying toolbox");
   try {
     await toolbox.destroy();
     ok(true, "Toolbox destroyed");
   } catch (e) {
     ok(false, "An exception occured while destroying toolbox");
     console.error(e);

--- a/devtools/client/inspector/test/browser_inspector_highlighter-05.js
+++ b/devtools/client/inspector/test/browser_inspector_highlighter-05.js
@@ -45,25 +45,20 @@ const TEST_URL =
     <body>
       <p>Slow page</p>
      </body>
   </html>
 `);
 
 add_task(async function() {
   info("Open the inspector to a blank page.");
-  const { inspector, tab, testActor } = await openInspectorForURL(
-    "about:blank"
-  );
-
-  const pageLoaded = BrowserTestUtils.browserLoaded(tab.linkedBrowser);
+  const { inspector, testActor } = await openInspectorForURL("about:blank");
 
   info("Navigate to the test url and waiting for the page to be loaded.");
-  await navigateTo(inspector, TEST_URL);
-  await pageLoaded;
+  await navigateTo(TEST_URL);
 
   info("Shows the box model highligher for the <p> node.");
   const divFront = await getNodeFront("p", inspector);
   await inspector.highlighter.showBoxModel(divFront);
 
   info("Check the node is highlighted.");
   is(
     await testActor.isHighlighting(),

--- a/devtools/client/inspector/test/browser_inspector_highlighter-eyedropper-xul.js
+++ b/devtools/client/inspector/test/browser_inspector_highlighter-eyedropper-xul.js
@@ -31,17 +31,17 @@ add_task(async function() {
   swatchEl.click();
   await onColorPickerReady;
 
   button = cPicker.tooltip.container.querySelector("#eyedropper-button");
   ok(isDisabled(button), "The button is disabled in the color picker");
 
   info("Navigate to a HTML document");
   const toolbarUpdated = inspector.once("inspector-toolbar-updated");
-  await navigateTo(inspector, TEST_URL_2);
+  await navigateTo(TEST_URL_2);
   await toolbarUpdated;
 
   info("Check the inspector toolbar in HTML document");
   button = inspector.panelDoc.querySelector("#inspector-eyedropper-toggle");
   ok(!isDisabled(button), "The button is enabled in the toolbar");
 
   info("Check the color picker in HTML document");
   // Find the color swatch in the rule-view.

--- a/devtools/client/inspector/test/browser_inspector_navigate_to_errors.js
+++ b/devtools/client/inspector/test/browser_inspector_navigate_to_errors.js
@@ -11,17 +11,17 @@ const TEST_URL_2 = "http://127.0.0.1:363
 const TEST_URL_3 = "http://www.wronguri.wronguri/";
 const TEST_URL_4 = "data:text/html,<html><body>test-doc-4</body></html>";
 
 add_task(async function() {
   // Open the inspector on a valid URL
   const { inspector, testActor } = await openInspectorForURL(TEST_URL_1);
 
   info("Navigate to closed port");
-  await navigateTo(inspector, TEST_URL_2);
+  await navigateTo(TEST_URL_2, { isErrorPage: true });
 
   const documentURI = await testActor.eval("document.documentURI;");
   ok(documentURI.startsWith("about:neterror"), "content is correct.");
 
   const hasPage = await getNodeFront("#test-doc-1", inspector);
   ok(
     !hasPage,
     "Inspector actor is no longer able to reach previous page DOM node"
@@ -37,27 +37,27 @@ add_task(async function() {
   let errorMsg = bundle.formatStringFromName("connectionFailure", [domain]);
   is(
     await getDisplayedNodeTextContent("#errorShortDescText", inspector),
     errorMsg,
     "Inpector really inspects the error page"
   );
 
   info("Navigate to unknown domain");
-  await navigateTo(inspector, TEST_URL_3);
+  await navigateTo(TEST_URL_3, { isErrorPage: true });
 
   domain = TEST_URL_3.match(/^http:\/\/(.*)\/$/)[1];
   errorMsg = bundle.formatStringFromName("dnsNotFound2", [domain]);
   is(
     await getDisplayedNodeTextContent("#errorShortDescText", inspector),
     errorMsg,
     "Inspector really inspects the new error page"
   );
 
   info("Navigate to a valid url");
-  await navigateTo(inspector, TEST_URL_4);
+  await navigateTo(TEST_URL_4);
 
   is(
     await getDisplayedNodeTextContent("body", inspector),
     "test-doc-4",
     "Inspector really inspects the valid url"
   );
 });

--- a/devtools/client/inspector/test/browser_inspector_navigation.js
+++ b/devtools/client/inspector/test/browser_inspector_navigation.js
@@ -20,17 +20,17 @@ const TEST_URL_4 =
   "data:text/html;charset=utf-8," + encodeURIComponent("<h1>bar</h1>");
 
 add_task(async function() {
   const { inspector, testActor } = await openInspectorForURL(TEST_URL_1);
 
   await selectNode("#i1", inspector);
 
   info("Navigating to a different page.");
-  await navigateTo(inspector, TEST_URL_2);
+  await navigateTo(TEST_URL_2);
 
   ok(true, "New page loaded");
   await selectNode("#i1", inspector);
 
   const markuploaded = inspector.once("markuploaded");
   const onUpdated = inspector.once("inspector-updated");
 
   info("Going back in history");
@@ -49,17 +49,17 @@ add_task(async function() {
 });
 
 add_task(async function() {
   const { inspector, testActor } = await openInspectorForURL(TEST_URL_3);
 
   await selectNode("img", inspector);
 
   info("Navigating to a different page.");
-  await navigateTo(inspector, TEST_URL_4);
+  await navigateTo(TEST_URL_4);
 
   ok(true, "New page loaded");
   await selectNode("#h1", inspector);
 
   const markuploaded = inspector.once("markuploaded");
   const onUpdated = inspector.once("inspector-updated");
 
   info("Going back in history");

--- a/devtools/client/inspector/test/browser_inspector_open_on_neterror.js
+++ b/devtools/client/inspector/test/browser_inspector_open_on_neterror.js
@@ -38,16 +38,16 @@ add_task(async function() {
 
   const documentURI = await testActor.eval("document.documentURI;");
   ok(
     documentURI.startsWith("about:neterror"),
     "content is really a net error page."
   );
 
   info("Navigate to a valid url");
-  await navigateTo(inspector, TEST_URL_2);
+  await navigateTo(TEST_URL_2);
 
   is(
     await getDisplayedNodeTextContent("body", inspector),
     "test-doc-2",
     "Inspector really inspects the valid url"
   );
 });

--- a/devtools/client/inspector/test/browser_inspector_select-last-selected.js
+++ b/devtools/client/inspector/test/browser_inspector_select-last-selected.js
@@ -84,12 +84,12 @@ add_task(async function() {
       const onUpdated = inspector.once("inspector-updated");
 
       await toolbox.target.reload();
       info("Waiting for inspector to be ready.");
       await markuploaded;
       await onNewRoot;
       await onUpdated;
     } else {
-      await navigateTo(inspector, url);
+      await navigateTo(url);
     }
   }
 });

--- a/devtools/client/inspector/test/head.js
+++ b/devtools/client/inspector/test/head.js
@@ -43,39 +43,16 @@ registerCleanupFunction(function() {
   EventUtils.synthesizeMouseAtPoint(
     window.innerWidth,
     1,
     { type: "mousemove" },
     window
   );
 });
 
-var navigateTo = async function(inspector, url) {
-  const markuploaded = inspector.once("markuploaded");
-  const onNewRoot = inspector.once("new-root");
-  const onUpdated = inspector.once("inspector-updated");
-  const onReloaded = inspector.once("reloaded");
-
-  info("Navigating to: " + url);
-  const target = inspector.toolbox.target;
-  await target.navigateTo({ url });
-
-  info("Waiting for markup view to load after navigation.");
-  await markuploaded;
-
-  info("Waiting for new root.");
-  await onNewRoot;
-
-  info("Waiting for inspector to update after new-root event.");
-  await onUpdated;
-
-  info("Waiting for inspector updates after page reload");
-  await onReloaded;
-};
-
 /**
  * Start the element picker and focus the content window.
  * @param {Toolbox} toolbox
  * @param {Boolean} skipFocus - Allow tests to bypass the focus event.
  */
 var startPicker = async function(toolbox, skipFocus) {
   info("Start the element picker");
   toolbox.win.focus();