Adding upstream version 115.7.0esr.upstream/115.7.0esr

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

19 files changed, 1434 insertions, 0 deletions

diff --git a/toolkit/components/viewsource/content/viewSourceUtils.js b/toolkit/components/viewsource/content/viewSourceUtils.js
new file mode 100644
index 0000000000..69d3eff287
--- /dev/null
+++ b/toolkit/components/viewsource/content/viewSourceUtils.js
@@ -0,0 +1,420 @@
+// -*- indent-tabs-mode: nil; js-indent-level: 2 -*-
+
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * To keep the global namespace safe, don't define global variables and
+ * functions in this file.
+ *
+ * This file silently depends on contentAreaUtils.js for getDefaultFileName
+ */
+
+ChromeUtils.defineESModuleGetters(this, {
+  PrivateBrowsingUtils: "resource://gre/modules/PrivateBrowsingUtils.sys.mjs",
+});
+
+var gViewSourceUtils = {
+  mnsIWebBrowserPersist: Ci.nsIWebBrowserPersist,
+  mnsIWebProgress: Ci.nsIWebProgress,
+  mnsIWebPageDescriptor: Ci.nsIWebPageDescriptor,
+
+  // Get the ViewSource actor for a browsing context.
+  getViewSourceActor(aBrowsingContext) {
+    return aBrowsingContext.currentWindowGlobal.getActor("ViewSource");
+  },
+
+  /**
+   * Get the ViewSourcePage actor.
+   * @param object An object with `browsingContext` field
+   */
+  getPageActor({ browsingContext }) {
+    return browsingContext.currentWindowGlobal.getActor("ViewSourcePage");
+  },
+
+  /**
+   * Opens the view source window.
+   *
+   * @param aArgs (required)
+   *        This Object can include the following properties:
+   *
+   *        URL (required):
+   *          A string URL for the page we'd like to view the source of.
+   *        browser (optional):
+   *          The browser containing the document that we would like to view the
+   *          source of. This is required if outerWindowID is passed.
+   *        outerWindowID (optional):
+   *          The outerWindowID of the content window containing the document that
+   *          we want to view the source of. Pass this if you want to attempt to
+   *          load the document source out of the network cache.
+   *        lineNumber (optional):
+   *          The line number to focus on once the source is loaded.
+   */
+  async viewSource(aArgs) {
+    // Check if external view source is enabled.  If so, try it.  If it fails,
+    // fallback to internal view source.
+    if (Services.prefs.getBoolPref("view_source.editor.external")) {
+      try {
+        await this.openInExternalEditor(aArgs);
+        return;
+      } catch (data) {}
+    }
+    // Try existing browsers first.
+    let browserWin = Services.wm.getMostRecentWindow("navigator:browser");
+    if (browserWin && browserWin.BrowserViewSourceOfDocument) {
+      browserWin.BrowserViewSourceOfDocument(aArgs);
+      return;
+    }
+    // No browser window created yet, try to create one.
+    let utils = this;
+    Services.ww.registerNotification(function onOpen(win, topic) {
+      if (
+        win.document.documentURI !== "about:blank" ||
+        topic !== "domwindowopened"
+      ) {
+        return;
+      }
+      Services.ww.unregisterNotification(onOpen);
+      win.addEventListener(
+        "load",
+        () => {
+          aArgs.viewSourceBrowser = win.gBrowser.selectedTab.linkedBrowser;
+          utils.viewSourceInBrowser(aArgs);
+        },
+        { once: true }
+      );
+    });
+    window.top.openWebLinkIn("about:blank", "current");
+  },
+
+  /**
+   * Displays view source in the provided <browser>.  This allows for non-window
+   * display methods, such as a tab from Firefox.
+   *
+   * @param aArgs
+   *        An object with the following properties:
+   *
+   *        URL (required):
+   *          A string URL for the page we'd like to view the source of.
+   *        viewSourceBrowser (required):
+   *          The browser to display the view source in.
+   *        browser (optional):
+   *          The browser containing the document that we would like to view the
+   *          source of. This is required if outerWindowID is passed.
+   *        outerWindowID (optional):
+   *          The outerWindowID of the content window containing the document that
+   *          we want to view the source of. Pass this if you want to attempt to
+   *          load the document source out of the network cache.
+   *        lineNumber (optional):
+   *          The line number to focus on once the source is loaded.
+   */
+  viewSourceInBrowser({
+    URL,
+    viewSourceBrowser,
+    browser,
+    outerWindowID,
+    lineNumber,
+  }) {
+    if (!URL) {
+      throw new Error("Must supply a URL when opening view source.");
+    }
+
+    if (browser) {
+      // If we're dealing with a remote browser, then the browser
+      // for view source needs to be remote as well.
+      if (viewSourceBrowser.remoteType != browser.remoteType) {
+        // In this base case, where we are handed a <browser> someone else is
+        // managing, we don't know for sure that it's safe to toggle remoteness.
+        // For view source in a window, this is overridden to actually do the
+        // flip if needed.
+        throw new Error("View source browser's remoteness mismatch");
+      }
+    } else if (outerWindowID) {
+      throw new Error("Must supply the browser if passing the outerWindowID");
+    }
+
+    let viewSourceActor = this.getViewSourceActor(
+      viewSourceBrowser.browsingContext
+    );
+    viewSourceActor.sendAsyncMessage("ViewSource:LoadSource", {
+      URL,
+      outerWindowID,
+      lineNumber,
+    });
+  },
+
+  /**
+   * Displays view source for a selection from some document in the provided
+   * <browser>.  This allows for non-window display methods, such as a tab from
+   * Firefox.
+   *
+   * @param aBrowsingContext:
+   *        The child browsing context containing the document to view the source of.
+   * @param aGetBrowserFn
+   *        A function that will return a browser to open the source in.
+   */
+  async viewPartialSourceInBrowser(aBrowsingContext, aGetBrowserFn) {
+    let sourceActor = this.getViewSourceActor(aBrowsingContext);
+    if (sourceActor) {
+      let data = await sourceActor.sendQuery("ViewSource:GetSelection", {});
+
+      let targetActor = this.getViewSourceActor(
+        aGetBrowserFn().browsingContext
+      );
+      targetActor.sendAsyncMessage("ViewSource:LoadSourceWithSelection", data);
+    }
+  },
+
+  buildEditorArgs(aPath, aLineNumber) {
+    // Determine the command line arguments to pass to the editor.
+    // We currently support a %LINE% placeholder which is set to the passed
+    // line number (or to 0 if there's none)
+    var editorArgs = [];
+    var args = Services.prefs.getCharPref("view_source.editor.args");
+    if (args) {
+      args = args.replace("%LINE%", aLineNumber || "0");
+      // add the arguments to the array (keeping quoted strings intact)
+      const argumentRE = /"([^"]+)"|(\S+)/g;
+      while (argumentRE.test(args)) {
+        editorArgs.push(RegExp.$1 || RegExp.$2);
+      }
+    }
+    editorArgs.push(aPath);
+    return editorArgs;
+  },
+
+  /**
+   * Opens an external editor with the view source content.
+   *
+   * @param aArgs (required)
+   *        This Object can include the following properties:
+   *
+   *        URL (required):
+   *          A string URL for the page we'd like to view the source of.
+   *        browser (optional):
+   *          The browser containing the document that we would like to view the
+   *          source of. This is required if outerWindowID is passed.
+   *        outerWindowID (optional):
+   *          The outerWindowID of the content window containing the document that
+   *          we want to view the source of. Pass this if you want to attempt to
+   *          load the document source out of the network cache.
+   *        lineNumber (optional):
+   *          The line number to focus on once the source is loaded.
+   *
+   * @return Promise
+   *        The promise will be resolved or rejected based on whether the
+   *        external editor attempt was successful.  Either way, the data object
+   *        is passed along as well.
+   */
+  openInExternalEditor(aArgs) {
+    return new Promise((resolve, reject) => {
+      let data;
+      let { URL, browser, lineNumber } = aArgs;
+      data = {
+        url: URL,
+        lineNumber,
+        isPrivate: false,
+      };
+      if (browser) {
+        data.doc = {
+          characterSet: browser.characterSet,
+          contentType: browser.documentContentType,
+          title: browser.contentTitle,
+          cookieJarSettings: browser.cookieJarSettings,
+        };
+        data.isPrivate = PrivateBrowsingUtils.isBrowserPrivate(browser);
+      }
+
+      try {
+        var editor = this.getExternalViewSourceEditor();
+        if (!editor) {
+          reject(data);
+          return;
+        }
+
+        // make a uri
+        var charset = data.doc ? data.doc.characterSet : null;
+        var uri = Services.io.newURI(data.url, charset);
+        data.uri = uri;
+
+        var path;
+        var contentType = data.doc ? data.doc.contentType : null;
+        var cookieJarSettings = data.doc ? data.doc.cookieJarSettings : null;
+        if (uri.scheme == "file") {
+          // it's a local file; we can open it directly
+          path = uri.QueryInterface(Ci.nsIFileURL).file.path;
+
+          var editorArgs = this.buildEditorArgs(path, data.lineNumber);
+          editor.runw(false, editorArgs, editorArgs.length);
+          resolve(data);
+        } else {
+          // set up the progress listener with what we know so far
+          this.viewSourceProgressListener.contentLoaded = false;
+          this.viewSourceProgressListener.editor = editor;
+          this.viewSourceProgressListener.resolve = resolve;
+          this.viewSourceProgressListener.reject = reject;
+          this.viewSourceProgressListener.data = data;
+
+          // without a page descriptor, loadPage has no chance of working. download the file.
+          var file = this.getTemporaryFile(uri, data.doc, contentType);
+          this.viewSourceProgressListener.file = file;
+
+          var webBrowserPersist = Cc[
+            "@mozilla.org/embedding/browser/nsWebBrowserPersist;1"
+          ].createInstance(this.mnsIWebBrowserPersist);
+          // the default setting is to not decode. we need to decode.
+          webBrowserPersist.persistFlags =
+            this.mnsIWebBrowserPersist.PERSIST_FLAGS_REPLACE_EXISTING_FILES;
+          webBrowserPersist.progressListener = this.viewSourceProgressListener;
+          let ssm = Services.scriptSecurityManager;
+          let principal = ssm.createContentPrincipal(
+            data.uri,
+            browser.contentPrincipal.originAttributes
+          );
+          webBrowserPersist.saveURI(
+            uri,
+            principal,
+            null,
+            null,
+            cookieJarSettings,
+            null,
+            null,
+            file,
+            Ci.nsIContentPolicy.TYPE_SAVEAS_DOWNLOAD,
+            data.isPrivate
+          );
+
+          let helperService = Cc[
+            "@mozilla.org/uriloader/external-helper-app-service;1"
+          ].getService(Ci.nsPIExternalAppLauncher);
+          if (data.isPrivate) {
+            // register the file to be deleted when possible
+            helperService.deleteTemporaryPrivateFileWhenPossible(file);
+          } else {
+            // register the file to be deleted on app exit
+            helperService.deleteTemporaryFileOnExit(file);
+          }
+        }
+      } catch (ex) {
+        // we failed loading it with the external editor.
+        console.error(ex);
+        reject(data);
+      }
+    });
+  },
+
+  // Returns nsIProcess of the external view source editor or null
+  getExternalViewSourceEditor() {
+    try {
+      let viewSourceAppPath = Services.prefs.getComplexValue(
+        "view_source.editor.path",
+        Ci.nsIFile
+      );
+      let editor = Cc["@mozilla.org/process/util;1"].createInstance(
+        Ci.nsIProcess
+      );
+      editor.init(viewSourceAppPath);
+
+      return editor;
+    } catch (ex) {
+      console.error(ex);
+    }
+
+    return null;
+  },
+
+  viewSourceProgressListener: {
+    mnsIWebProgressListener: Ci.nsIWebProgressListener,
+
+    QueryInterface: ChromeUtils.generateQI([
+      "nsIWebProgressListener",
+      "nsISupportsWeakReference",
+    ]),
+
+    destroy() {
+      this.editor = null;
+      this.resolve = null;
+      this.reject = null;
+      this.data = null;
+      this.file = null;
+    },
+
+    // This listener is used both for tracking the progress of an HTML parse
+    // in one case and for tracking the progress of nsIWebBrowserPersist in
+    // another case.
+    onStateChange(aProgress, aRequest, aFlag, aStatus) {
+      // once it's done loading...
+      if (aFlag & this.mnsIWebProgressListener.STATE_STOP && aStatus == 0) {
+        // We aren't waiting for the parser. Instead, we are waiting for
+        // an nsIWebBrowserPersist.
+        this.onContentLoaded();
+      }
+      return 0;
+    },
+
+    onContentLoaded() {
+      // The progress listener may call this multiple times, so be sure we only
+      // run once.
+      if (this.contentLoaded) {
+        return;
+      }
+      try {
+        if (!this.file) {
+          throw new Error("View-source progress listener should have a file!");
+        }
+
+        var editorArgs = gViewSourceUtils.buildEditorArgs(
+          this.file.path,
+          this.data.lineNumber
+        );
+        this.editor.runw(false, editorArgs, editorArgs.length);
+
+        this.contentLoaded = true;
+        this.resolve(this.data);
+      } catch (ex) {
+        // we failed loading it with the external editor.
+        console.error(ex);
+        this.reject(this.data);
+      } finally {
+        this.destroy();
+      }
+    },
+
+    editor: null,
+    resolve: null,
+    reject: null,
+    data: null,
+    file: null,
+  },
+
+  // returns an nsIFile for the passed document in the system temp directory
+  getTemporaryFile(aURI, aDocument, aContentType) {
+    // include contentAreaUtils.js in our own context when we first need it
+    if (!this._caUtils) {
+      this._caUtils = {};
+      Services.scriptloader.loadSubScript(
+        "chrome://global/content/contentAreaUtils.js",
+        this._caUtils
+      );
+    }
+
+    var fileName = this._caUtils.getDefaultFileName(
+      null,
+      aURI,
+      aDocument,
+      null
+    );
+
+    const mimeService = Cc["@mozilla.org/mime;1"].getService(Ci.nsIMIMEService);
+    fileName = mimeService.validateFileNameForSaving(
+      fileName,
+      aContentType,
+      mimeService.VALIDATE_DEFAULT
+    );
+
+    var tempFile = Services.dirsvc.get("TmpD", Ci.nsIFile);
+    tempFile.append(fileName);
+    return tempFile;
+  },
+};
diff --git a/toolkit/components/viewsource/jar.mn b/toolkit/components/viewsource/jar.mn
new file mode 100644
index 0000000000..e483f3080a
--- /dev/null
+++ b/toolkit/components/viewsource/jar.mn
@@ -0,0 +1,6 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+toolkit.jar:
+  content/global/viewSourceUtils.js         (content/viewSourceUtils.js)
diff --git a/toolkit/components/viewsource/moz.build b/toolkit/components/viewsource/moz.build
new file mode 100644
index 0000000000..1f13fe6e56
--- /dev/null
+++ b/toolkit/components/viewsource/moz.build
@@ -0,0 +1,13 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+BROWSER_CHROME_MANIFESTS += ["test/browser/browser.ini"]
+MOCHITEST_CHROME_MANIFESTS += ["test/chrome.ini"]
+
+JAR_MANIFESTS += ["jar.mn"]
+
+with Files("**"):
+    BUG_COMPONENT = ("Toolkit", "View Source")
diff --git a/toolkit/components/viewsource/test/browser/browser.ini b/toolkit/components/viewsource/test/browser/browser.ini
new file mode 100644
index 0000000000..4ac477c7c1
--- /dev/null
+++ b/toolkit/components/viewsource/test/browser/browser.ini
@@ -0,0 +1,22 @@
+[DEFAULT]
+support-files = head.js
+  file_bug464222.html
+
+[browser_bug464222.js]
+https_first_disabled = true
+[browser_viewsource_newwindow.js]
+https_first_disabled = true
+[browser_bug713810.js]
+[browser_contextmenu.js]
+skip-if =
+  os == "win" && processor == "aarch64"  # disabled on aarch64 due to 1531590
+  fission && os == "mac" && !debug  # Bug 1713913 - new Fission platform triage
+[browser_gotoline.js]
+[browser_open_docgroup.js]
+[browser_partialsource.js]
+skip-if =
+  fission && os == "mac" && !debug  # Bug 1713913 - new Fission platform triage
+[browser_srcdoc.js]
+[browser_validatefilename.js]
+[browser_viewsourceprefs.js]
+skip-if = socketprocess_networking && os == "linux" && !debug
diff --git a/toolkit/components/viewsource/test/browser/browser_bug464222.js b/toolkit/components/viewsource/test/browser/browser_bug464222.js
new file mode 100644
index 0000000000..b14f35e61a
--- /dev/null
+++ b/toolkit/components/viewsource/test/browser/browser_bug464222.js
@@ -0,0 +1,17 @@
+const source =
+  "http://example.com/browser/toolkit/components/viewsource/test/browser/file_bug464222.html";
+
+add_task(async function () {
+  let viewSourceTab = await openDocumentSelect(source, "a");
+
+  let href = await SpecialPowers.spawn(
+    viewSourceTab.linkedBrowser,
+    [],
+    async function () {
+      return content.document.querySelectorAll("a[href]")[0].href;
+    }
+  );
+
+  is(href, "view-source:" + source, "Relative links broken?");
+  gBrowser.removeTab(viewSourceTab);
+});
diff --git a/toolkit/components/viewsource/test/browser/browser_bug713810.js b/toolkit/components/viewsource/test/browser/browser_bug713810.js
new file mode 100644
index 0000000000..b798f6cd10
--- /dev/null
+++ b/toolkit/components/viewsource/test/browser/browser_bug713810.js
@@ -0,0 +1,31 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+const source =
+  '<html xmlns="http://www.w3.org/1999/xhtml"><body><p>This is a paragraph.</p></body></html>';
+
+add_task(async function () {
+  let viewSourceTab = await openDocumentSelect("data:text/html," + source, "p");
+  await SpecialPowers.spawn(viewSourceTab.linkedBrowser, [], async function () {
+    Assert.equal(
+      content.document.body.textContent,
+      "<p>This is a paragraph.</p>",
+      "Correct source for text/html"
+    );
+  });
+  gBrowser.removeTab(viewSourceTab);
+
+  viewSourceTab = await openDocumentSelect(
+    "data:application/xhtml+xml," + source,
+    "p"
+  );
+  await SpecialPowers.spawn(viewSourceTab.linkedBrowser, [], async function () {
+    Assert.equal(
+      content.document.body.textContent,
+      '<p xmlns="http://www.w3.org/1999/xhtml">This is a paragraph.</p>',
+      "Correct source for application/xhtml+xml"
+    );
+  });
+  gBrowser.removeTab(viewSourceTab);
+});
diff --git a/toolkit/components/viewsource/test/browser/browser_contextmenu.js b/toolkit/components/viewsource/test/browser/browser_contextmenu.js
new file mode 100644
index 0000000000..afc8ab8c84
--- /dev/null
+++ b/toolkit/components/viewsource/test/browser/browser_contextmenu.js
@@ -0,0 +1,115 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+var source =
+  "data:text/html,text<link%20href='http://example.com/'%20/>more%20text<a%20href='mailto:abc@def.ghi'>email</a>";
+var gViewSourceWindow, gContextMenu, gCopyLinkMenuItem, gCopyEmailMenuItem;
+
+var expectedData = [];
+
+add_task(async function () {
+  // Full source in view source tab
+  let newTab = await openDocument(source);
+  await onViewSourceWindowOpen(window);
+
+  let contextMenu = document.getElementById("contentAreaContextMenu");
+
+  for (let test of expectedData) {
+    await checkMenuItems(contextMenu, test[0], test[1], test[2], test[3]);
+  }
+
+  gBrowser.removeTab(newTab);
+
+  // Selection source in view source tab
+  expectedData = [];
+  newTab = await openDocumentSelect(source, "body");
+  await onViewSourceWindowOpen(window);
+
+  contextMenu = document.getElementById("contentAreaContextMenu");
+
+  for (let test of expectedData) {
+    await checkMenuItems(contextMenu, test[0], test[1], test[2], test[3]);
+  }
+
+  gBrowser.removeTab(newTab);
+});
+
+async function onViewSourceWindowOpen(aWindow) {
+  gViewSourceWindow = aWindow;
+
+  gCopyLinkMenuItem = aWindow.document.getElementById("context-copylink");
+  gCopyEmailMenuItem = aWindow.document.getElementById("context-copyemail");
+
+  let browser = gBrowser.selectedBrowser;
+  await SpecialPowers.spawn(browser, [], async function (arg) {
+    let tags = content.document.querySelectorAll("a[href]");
+    Assert.equal(
+      tags[0].href,
+      "view-source:http://example.com/",
+      "Link has correct href"
+    );
+    Assert.equal(tags[1].href, "mailto:abc@def.ghi", "Link has correct href");
+  });
+
+  expectedData.push(["a[href]", true, false, "http://example.com/"]);
+  expectedData.push(["a[href^=mailto]", false, true, "abc@def.ghi"]);
+  expectedData.push(["span", false, false, null]);
+}
+
+async function checkMenuItems(
+  contextMenu,
+  selector,
+  copyLinkExpected,
+  copyEmailExpected,
+  expectedClipboardContent
+) {
+  let browser = gBrowser.selectedBrowser;
+  await SpecialPowers.spawn(browser, [{ selector }], async function (arg) {
+    content.document.querySelector(arg.selector).scrollIntoView();
+  });
+
+  let popupShownPromise = BrowserTestUtils.waitForEvent(
+    contextMenu,
+    "popupshown"
+  );
+  await BrowserTestUtils.synthesizeMouseAtCenter(
+    selector,
+    { type: "contextmenu", button: 2 },
+    browser
+  );
+  await popupShownPromise;
+
+  is(
+    gCopyLinkMenuItem.hidden,
+    !copyLinkExpected,
+    "Copy link menuitem is " + (copyLinkExpected ? "not hidden" : "hidden")
+  );
+  is(
+    gCopyEmailMenuItem.hidden,
+    !copyEmailExpected,
+    "Copy email menuitem is " + (copyEmailExpected ? "not hidden" : "hidden")
+  );
+
+  if (copyLinkExpected || copyEmailExpected) {
+    await new Promise((resolve, reject) => {
+      waitForClipboard(
+        expectedClipboardContent,
+        function () {
+          contextMenu.activateItem(
+            copyLinkExpected ? gCopyLinkMenuItem : gCopyEmailMenuItem
+          );
+        },
+        resolve,
+        reject
+      );
+    });
+  } else {
+    let popupHiddenPromise = BrowserTestUtils.waitForEvent(
+      contextMenu,
+      "popuphidden"
+    );
+    contextMenu.hidePopup();
+    await popupHiddenPromise;
+  }
+}
diff --git a/toolkit/components/viewsource/test/browser/browser_gotoline.js b/toolkit/components/viewsource/test/browser/browser_gotoline.js
new file mode 100644
index 0000000000..000b2c6876
--- /dev/null
+++ b/toolkit/components/viewsource/test/browser/browser_gotoline.js
@@ -0,0 +1,37 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+var content = "line 1\nline 2\nline 3";
+
+add_task(async function () {
+  // First test with text with the text/html mimetype.
+  let tab = await openDocument("data:text/html," + encodeURIComponent(content));
+  await checkViewSource(tab);
+  gBrowser.removeTab(tab);
+
+  tab = await openDocument("data:text/plain," + encodeURIComponent(content));
+  await checkViewSource(tab);
+  gBrowser.removeTab(tab);
+});
+
+var checkViewSource = async function (aTab) {
+  let browser = aTab.linkedBrowser;
+  await SpecialPowers.spawn(browser, [content], async function (text) {
+    is(content.document.body.textContent, text, "Correct content loaded");
+  });
+
+  for (let i = 1; i <= 3; i++) {
+    browser.sendMessageToActor(
+      "ViewSource:GoToLine",
+      {
+        lineNumber: i,
+      },
+      "ViewSourcePage"
+    );
+    await SpecialPowers.spawn(browser, [i], async function (i) {
+      let selection = content.getSelection();
+      Assert.equal(selection.toString(), "line " + i, "Correct text selected");
+    });
+  }
+};
diff --git a/toolkit/components/viewsource/test/browser/browser_open_docgroup.js b/toolkit/components/viewsource/test/browser/browser_open_docgroup.js
new file mode 100644
index 0000000000..071635b998
--- /dev/null
+++ b/toolkit/components/viewsource/test/browser/browser_open_docgroup.js
@@ -0,0 +1,41 @@
+"use strict";
+
+/**
+ * Very basic smoketests for the View Source feature, which also
+ * forces on the DocGroup mismatch check that was added in
+ * bug 1340719.
+ */
+
+add_setup(async function () {
+  await SpecialPowers.pushPrefEnv({
+    set: [["extensions.throw_on_docgroup_mismatch.enabled", true]],
+  });
+});
+
+/**
+ * Tests that we can open View Source in a tab.
+ */
+add_task(async function test_view_source_in_tab() {
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: "http://example.com",
+    },
+    async function (browser) {
+      let sourceTab = await openViewSourceForBrowser(browser);
+      let sourceBrowser = sourceTab.linkedBrowser;
+
+      await SpecialPowers.spawn(sourceBrowser, [], async function () {
+        Assert.equal(
+          content.document.body.id,
+          "viewsource",
+          "View source mode enabled"
+        );
+      });
+
+      BrowserTestUtils.removeTab(sourceTab);
+    }
+  );
+
+  await SpecialPowers.popPrefEnv();
+});
diff --git a/toolkit/components/viewsource/test/browser/browser_partialsource.js b/toolkit/components/viewsource/test/browser/browser_partialsource.js
new file mode 100644
index 0000000000..d57a265b08
--- /dev/null
+++ b/toolkit/components/viewsource/test/browser/browser_partialsource.js
@@ -0,0 +1,46 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+const frameSource =
+  "<a href='about:mozilla'>some text</a><a id='other' href='about:about'>other text</a>";
+const sources = [
+  `<html><iframe id="f" srcdoc="${frameSource}"></iframe></html>`,
+  `<html><iframe id="f" src="https://example.com/document-builder.sjs?html=${frameSource}"></iframe></html>`,
+];
+
+add_task(async function partial_source() {
+  for (let source of sources) {
+    let tab = await BrowserTestUtils.openNewForegroundTab(
+      gBrowser,
+      "data:text/html," + source
+    );
+
+    let frameBC = gBrowser.selectedBrowser.browsingContext.children[0];
+
+    await SpecialPowers.spawn(frameBC, [], () => {
+      let element = content.document.getElementById("other");
+      content.focus();
+      content.getSelection().selectAllChildren(element);
+    });
+
+    let sourceTab = await openViewPartialSource("#other", frameBC);
+
+    let browser = gBrowser.selectedBrowser;
+    let textContent = await SpecialPowers.spawn(browser, [], async function () {
+      return content.document.body.textContent;
+    });
+    is(
+      textContent,
+      '<a id="other" href="about:about">other text</a>',
+      "Correct content loaded"
+    );
+    let selection = await SpecialPowers.spawn(browser, [], async function () {
+      return String(content.getSelection());
+    });
+    is(selection, "other text", "Correct text selected");
+
+    gBrowser.removeTab(sourceTab);
+    gBrowser.removeTab(tab);
+  }
+});
diff --git a/toolkit/components/viewsource/test/browser/browser_srcdoc.js b/toolkit/components/viewsource/test/browser/browser_srcdoc.js
new file mode 100644
index 0000000000..fbb07dd0ad
--- /dev/null
+++ b/toolkit/components/viewsource/test/browser/browser_srcdoc.js
@@ -0,0 +1,28 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+const frameSource = `<a href="about:mozilla">good</a>`;
+const source = `<html><iframe srcdoc='${frameSource}' id="f"></iframe></html>`;
+
+add_task(async function () {
+  let url = `data:text/html,${source}`;
+  await BrowserTestUtils.withNewTab({ gBrowser, url }, checkFrameSource);
+});
+
+async function checkFrameSource() {
+  let sourceTab = await openViewFrameSourceTab("#f");
+  registerCleanupFunction(function () {
+    gBrowser.removeTab(sourceTab);
+  });
+
+  let browser = gBrowser.selectedBrowser;
+  let textContent = await SpecialPowers.spawn(browser, [], async function () {
+    return content.document.body.textContent;
+  });
+  is(textContent, frameSource, "Correct content loaded");
+  let id = await SpecialPowers.spawn(browser, [], async function () {
+    return content.document.body.id;
+  });
+  is(id, "viewsource", "View source mode enabled");
+}
diff --git a/toolkit/components/viewsource/test/browser/browser_validatefilename.js b/toolkit/components/viewsource/test/browser/browser_validatefilename.js
new file mode 100644
index 0000000000..57699df733
--- /dev/null
+++ b/toolkit/components/viewsource/test/browser/browser_validatefilename.js
@@ -0,0 +1,68 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+add_task(async function () {
+  let tests = [
+    {
+      uri: "data:text/html,Test",
+      basename: "Untitled",
+    },
+    {
+      uri: "data:text/html,<title>Hello There</title>Test",
+      basename: "Hello There",
+    },
+  ];
+
+  for (let test of tests) {
+    await BrowserTestUtils.withNewTab(test.uri, async browser => {
+      let doc = {
+        characterSet: browser.characterSet,
+        contentType: browser.documentContentType,
+        title: browser.contentTitle,
+      };
+
+      let fl = gViewSourceUtils.getTemporaryFile(
+        browser.currentURI,
+        doc,
+        "text/html"
+      );
+      // Some versions of Windows will crop the extension to three characters so allow both forms.
+      ok(
+        fl.leafName == test.basename + ".htm" ||
+          fl.leafName == test.basename + ".html",
+        "filename title for " + test.basename + " html"
+      );
+
+      doc.contentType = "application/xhtml+xml";
+      fl = gViewSourceUtils.getTemporaryFile(
+        browser.currentURI,
+        doc,
+        "application/xhtml+xml"
+      );
+      ok(
+        fl.leafName == test.basename + ".xht" ||
+          fl.leafName == test.basename + ".xhtml",
+        "filename title for " + test.basename + " xhtml"
+      );
+    });
+  }
+
+  let fl = gViewSourceUtils.getTemporaryFile(
+    Services.io.newURI("http://www.example.com/simple"),
+    null,
+    "text/html"
+  );
+  ok(
+    fl.leafName == "simple.htm" || fl.leafName == "simple.html",
+    "filename title for simple"
+  );
+
+  fl = gViewSourceUtils.getTemporaryFile(
+    Services.io.newURI("http://www.example.com/samplefile.txt"),
+    null,
+    "text/html"
+  );
+  is(fl.leafName, "samplefile.txt", "filename title for samplefile");
+});
diff --git a/toolkit/components/viewsource/test/browser/browser_viewsource_newwindow.js b/toolkit/components/viewsource/test/browser/browser_viewsource_newwindow.js
new file mode 100644
index 0000000000..8a38d94719
--- /dev/null
+++ b/toolkit/components/viewsource/test/browser/browser_viewsource_newwindow.js
@@ -0,0 +1,102 @@
+/**
+ * Waits for a View Source window to be opened at a particular
+ * URL.
+ *
+ * @param {string} expectedURL The view-source: URL that's expected.
+ * @resolves {DOM Window} The window that was opened.
+ * @returns {Promise}
+ */
+async function waitForNewViewSourceWindow(expectedURL) {
+  let win = await BrowserTestUtils.domWindowOpened();
+  await BrowserTestUtils.waitForEvent(win, "EndSwapDocShells", true);
+  let browser = win.gBrowser.selectedBrowser;
+  if (browser.currentURI.spec != expectedURL) {
+    await BrowserTestUtils.browserLoaded(browser, false, expectedURL);
+  }
+  return win;
+}
+
+/**
+ * When view_source.tab is set to false, view source should
+ * open in new browser window instead of new tab.
+ */
+add_task(async function () {
+  await SpecialPowers.pushPrefEnv({
+    set: [["view_source.tab", false]],
+  });
+
+  const PAGE = "http://example.com/";
+  await BrowserTestUtils.withNewTab(
+    {
+      url: PAGE,
+      gBrowser,
+    },
+    async browser => {
+      let winPromise = waitForNewViewSourceWindow("view-source:" + PAGE);
+      BrowserViewSource(browser);
+      let win = await winPromise;
+
+      ok(win, "View Source opened up in a new window.");
+      await BrowserTestUtils.closeWindow(win);
+    }
+  );
+});
+
+/**
+ * When view_source.tab is set to false, view partial source
+ * should open up in new browser window instead of new tab.
+ */
+add_task(async function () {
+  await SpecialPowers.pushPrefEnv({
+    set: [["view_source.tab", false]],
+  });
+
+  const para = "<p>test</p>";
+  const source = `<html><body>${para}</body></html>`;
+  await BrowserTestUtils.withNewTab(
+    {
+      url: "data:text/html," + source,
+      gBrowser,
+    },
+    async browser => {
+      let winPromise = waitForNewViewSourceWindow(
+        "view-source:data:text/html;charset=utf-8,%3Cp%3E%EF%B7%90test%EF%B7%AF%3C%2Fp%3E"
+      );
+      await SpecialPowers.spawn(
+        gBrowser.selectedBrowser,
+        [],
+        async function (arg) {
+          let element = content.document.querySelector("p");
+          content.getSelection().selectAllChildren(element);
+        }
+      );
+
+      let contentAreaContextMenuPopup = document.getElementById(
+        "contentAreaContextMenu"
+      );
+      let popupShownPromise = BrowserTestUtils.waitForEvent(
+        contentAreaContextMenuPopup,
+        "popupshown"
+      );
+      await BrowserTestUtils.synthesizeMouseAtCenter(
+        "p",
+        { type: "contextmenu", button: 2 },
+        gBrowser.selectedBrowser
+      );
+      await popupShownPromise;
+
+      let popupHiddenPromise = BrowserTestUtils.waitForEvent(
+        contentAreaContextMenuPopup,
+        "popuphidden"
+      );
+      let item = document.getElementById("context-viewpartialsource-selection");
+      contentAreaContextMenuPopup.activateItem(item);
+      await popupHiddenPromise;
+      dump("Before winPromise");
+      let win = await winPromise;
+      dump("After winPromise");
+      ok(win, "View Partial Source opened up in a new window.");
+      await BrowserTestUtils.closeWindow(win);
+    }
+  );
+});
diff --git a/toolkit/components/viewsource/test/browser/browser_viewsourceprefs.js b/toolkit/components/viewsource/test/browser/browser_viewsourceprefs.js
new file mode 100644
index 0000000000..e155a9c87e
--- /dev/null
+++ b/toolkit/components/viewsource/test/browser/browser_viewsourceprefs.js
@@ -0,0 +1,203 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+var plaintextURL = "data:text/plain,hello+world";
+var htmlURL = "about:mozilla";
+
+add_setup(async function () {
+  registerCleanupFunction(function () {
+    SpecialPowers.clearUserPref("view_source.tab_size");
+    SpecialPowers.clearUserPref("view_source.wrap_long_lines");
+    SpecialPowers.clearUserPref("view_source.syntax_highlight");
+  });
+});
+
+add_task(async function () {
+  await exercisePrefs(plaintextURL, false);
+  await exercisePrefs(htmlURL, true);
+});
+
+const contextMenu = document.getElementById("contentAreaContextMenu");
+async function openContextMenu(browser) {
+  info("Opening context menu");
+  const popupShownPromise = BrowserTestUtils.waitForEvent(
+    contextMenu,
+    "popupshown"
+  );
+  await BrowserTestUtils.synthesizeMouseAtCenter(
+    "html",
+    { type: "contextmenu", button: 2 },
+    browser
+  );
+  await popupShownPromise;
+  info("Opened context menu");
+}
+
+async function closeContextMenu() {
+  const popupHiddenPromise = BrowserTestUtils.waitForEvent(
+    contextMenu,
+    "popuphidden"
+  );
+  contextMenu.hidePopup();
+  await popupHiddenPromise;
+}
+
+async function simulateClick(id) {
+  const popupHiddenPromise = BrowserTestUtils.waitForEvent(
+    contextMenu,
+    "popuphidden"
+  );
+  contextMenu.activateItem(document.getElementById(id));
+  await popupHiddenPromise;
+}
+
+function getAttribute(id, attribute) {
+  let item = document.getElementById(id);
+  return item.getAttribute(attribute);
+}
+
+var exercisePrefs = async function (source, highlightable) {
+  let tab = await openDocument(source);
+  let browser = tab.linkedBrowser;
+
+  const wrapMenuItem = "context-viewsource-wrapLongLines";
+  const syntaxMenuItem = "context-viewsource-highlightSyntax";
+
+  // Test the default states of these menu items.
+  await checkStyle(browser, "-moz-tab-size", 4);
+  await openContextMenu(browser);
+  await checkStyle(browser, "white-space", "pre");
+  await checkHighlight(browser, highlightable);
+  is(
+    getAttribute(wrapMenuItem, "checked"),
+    "false",
+    "Wrap menu item not checked by default"
+  );
+  is(
+    getAttribute(syntaxMenuItem, "checked"),
+    "true",
+    "Syntax menu item checked by default"
+  );
+  await closeContextMenu();
+
+  // Next, test that the Wrap Long Lines menu item works.
+  let prefReady = waitForPrefChange("view_source.wrap_long_lines");
+  await openContextMenu(browser);
+  await simulateClick(wrapMenuItem);
+  await openContextMenu(browser);
+  await checkStyle(browser, "white-space", "pre-wrap");
+  is(getAttribute(wrapMenuItem, "checked"), "true", "Wrap menu item checked");
+  await prefReady;
+  is(
+    SpecialPowers.getBoolPref("view_source.wrap_long_lines"),
+    true,
+    "Wrap pref set"
+  );
+  await closeContextMenu();
+
+  prefReady = waitForPrefChange("view_source.wrap_long_lines");
+  await openContextMenu(browser);
+  await simulateClick(wrapMenuItem);
+  await openContextMenu(browser);
+  await checkStyle(browser, "white-space", "pre");
+  is(
+    getAttribute(wrapMenuItem, "checked"),
+    "false",
+    "Wrap menu item unchecked"
+  );
+  await prefReady;
+  is(
+    SpecialPowers.getBoolPref("view_source.wrap_long_lines"),
+    false,
+    "Wrap pref set"
+  );
+  await closeContextMenu();
+
+  // Check that the Syntax Highlighting menu item works.
+  prefReady = waitForPrefChange("view_source.syntax_highlight");
+  await openContextMenu(browser);
+  await simulateClick(syntaxMenuItem);
+  await openContextMenu(browser);
+  await checkHighlight(browser, false);
+  is(
+    getAttribute(syntaxMenuItem, "checked"),
+    "false",
+    "Syntax menu item unchecked"
+  );
+  await prefReady;
+  is(
+    SpecialPowers.getBoolPref("view_source.syntax_highlight"),
+    false,
+    "Syntax highlighting pref set"
+  );
+  await closeContextMenu();
+
+  prefReady = waitForPrefChange("view_source.syntax_highlight");
+  await openContextMenu(browser);
+  await simulateClick(syntaxMenuItem);
+  await openContextMenu(browser);
+  await checkHighlight(browser, highlightable);
+  is(
+    getAttribute(syntaxMenuItem, "checked"),
+    "true",
+    "Syntax menu item checked"
+  );
+  await prefReady;
+  is(
+    SpecialPowers.getBoolPref("view_source.syntax_highlight"),
+    true,
+    "Syntax highlighting pref set"
+  );
+  await closeContextMenu();
+  gBrowser.removeTab(tab);
+
+  // Open a new view-source window to check that the prefs are obeyed.
+  SpecialPowers.setIntPref("view_source.tab_size", 2);
+  SpecialPowers.setBoolPref("view_source.wrap_long_lines", true);
+  SpecialPowers.setBoolPref("view_source.syntax_highlight", false);
+
+  tab = await openDocument(source);
+  browser = tab.linkedBrowser;
+
+  await checkStyle(browser, "-moz-tab-size", 2);
+  await openContextMenu(browser);
+  await checkStyle(browser, "white-space", "pre-wrap");
+  await checkHighlight(browser, false);
+  is(getAttribute(wrapMenuItem, "checked"), "true", "Wrap menu item checked");
+  is(
+    getAttribute(syntaxMenuItem, "checked"),
+    "false",
+    "Syntax menu item unchecked"
+  );
+
+  SpecialPowers.clearUserPref("view_source.tab_size");
+  SpecialPowers.clearUserPref("view_source.wrap_long_lines");
+  SpecialPowers.clearUserPref("view_source.syntax_highlight");
+
+  await closeContextMenu();
+  gBrowser.removeTab(tab);
+};
+
+var checkStyle = async function (browser, styleProperty, expected) {
+  let value = await SpecialPowers.spawn(
+    browser,
+    [styleProperty],
+    async function (styleProperty) {
+      let style = content.getComputedStyle(content.document.body);
+      return style.getPropertyValue(styleProperty);
+    }
+  );
+  is(value, "" + expected, "Correct value of " + styleProperty);
+};
+
+var checkHighlight = async function (browser, expected) {
+  let highlighted = await SpecialPowers.spawn(browser, [], async function () {
+    let spans = content.document.getElementsByTagName("span");
+    return Array.prototype.some.call(spans, span => {
+      let style = content.getComputedStyle(span);
+      return style.getPropertyValue("color") !== "rgb(0, 0, 0)";
+    });
+  });
+  is(highlighted, expected, "Syntax highlighting " + (expected ? "on" : "off"));
+};
diff --git a/toolkit/components/viewsource/test/browser/file_bug464222.html b/toolkit/components/viewsource/test/browser/file_bug464222.html
new file mode 100644
index 0000000000..f3b00949c7
--- /dev/null
+++ b/toolkit/components/viewsource/test/browser/file_bug464222.html
@@ -0,0 +1 @@
+<a href="file_bug464222.html">I'm a link</a>
diff --git a/toolkit/components/viewsource/test/browser/head.js b/toolkit/components/viewsource/test/browser/head.js
new file mode 100644
index 0000000000..7ecde2ec51
--- /dev/null
+++ b/toolkit/components/viewsource/test/browser/head.js
@@ -0,0 +1,234 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+var { PromiseUtils } = ChromeUtils.importESModule(
+  "resource://gre/modules/PromiseUtils.sys.mjs"
+);
+const { Preferences } = ChromeUtils.importESModule(
+  "resource://gre/modules/Preferences.sys.mjs"
+);
+
+/**
+ * Wait for view source tab after calling given function to open it.
+ *
+ * @param open - a function to open view source.
+ * @returns the new tab which shows the source.
+ */
+async function waitForViewSourceTab(open) {
+  let sourceLoadedPromise;
+  let tabPromise;
+
+  tabPromise = new Promise(resolve => {
+    gBrowser.tabContainer.addEventListener(
+      "TabOpen",
+      event => {
+        let tab = event.target;
+        sourceLoadedPromise = waitForSourceLoaded(tab);
+        resolve(tab);
+      },
+      { once: true }
+    );
+  });
+
+  await open();
+
+  let tab = await tabPromise;
+  await sourceLoadedPromise;
+  return tab;
+}
+
+/**
+ * Opens view source for a browser.
+ *
+ * @param browser - the <xul:browser> to open view source for.
+ * @returns the new tab which shows the source.
+ */
+function openViewSourceForBrowser(browser) {
+  return waitForViewSourceTab(() => {
+    window.BrowserViewSource(browser);
+  });
+}
+
+/**
+ * Opens a view source tab. (View Source)
+ * within the currently selected browser in gBrowser.
+ *
+ * @returns the new tab which shows the source.
+ */
+async function openViewSource() {
+  let contentAreaContextMenuPopup = document.getElementById(
+    "contentAreaContextMenu"
+  );
+  let popupShownPromise = BrowserTestUtils.waitForEvent(
+    contentAreaContextMenuPopup,
+    "popupshown"
+  );
+  await BrowserTestUtils.synthesizeMouseAtCenter(
+    "body",
+    { type: "contextmenu", button: 2 },
+    gBrowser.selectedBrowser
+  );
+  await popupShownPromise;
+
+  return waitForViewSourceTab(async () => {
+    let popupHiddenPromise = BrowserTestUtils.waitForEvent(
+      contentAreaContextMenuPopup,
+      "popuphidden"
+    );
+    contentAreaContextMenuPopup.activateItem(
+      document.getElementById("context-viewsource")
+    );
+    await popupHiddenPromise;
+  });
+}
+
+/**
+ * Opens a view source tab for a selection (View Selection Source)
+ * within the currently selected browser in gBrowser.
+ *
+ * @param aCSSSelector - used to specify a node within the selection to
+ *                       view the source of. It is expected that this node is
+ *                       within an existing selection.
+ * @param aBrowsingContext - browsing context containing a subframe (optional).
+ * @returns the new tab which shows the source.
+ */
+async function openViewPartialSource(
+  aCSSSelector,
+  aBrowsingContext = gBrowser.selectedBrowser
+) {
+  let contentAreaContextMenuPopup = document.getElementById(
+    "contentAreaContextMenu"
+  );
+  let popupShownPromise = BrowserTestUtils.waitForEvent(
+    contentAreaContextMenuPopup,
+    "popupshown"
+  );
+  await BrowserTestUtils.synthesizeMouseAtCenter(
+    aCSSSelector,
+    { type: "contextmenu", button: 2 },
+    aBrowsingContext
+  );
+  await popupShownPromise;
+
+  return waitForViewSourceTab(async () => {
+    let popupHiddenPromise = BrowserTestUtils.waitForEvent(
+      contentAreaContextMenuPopup,
+      "popuphidden"
+    );
+    let item = document.getElementById("context-viewpartialsource-selection");
+    contentAreaContextMenuPopup.activateItem(item);
+    await popupHiddenPromise;
+  });
+}
+
+/**
+ * Opens a view source tab for a frame (View Frame Source) within the
+ * currently selected browser in gBrowser.
+ *
+ * @param aCSSSelector - used to specify the frame to view the source of.
+ * @returns the new tab which shows the source.
+ */
+async function openViewFrameSourceTab(aCSSSelector) {
+  let contentAreaContextMenuPopup = document.getElementById(
+    "contentAreaContextMenu"
+  );
+  let popupShownPromise = BrowserTestUtils.waitForEvent(
+    contentAreaContextMenuPopup,
+    "popupshown"
+  );
+  await BrowserTestUtils.synthesizeMouseAtCenter(
+    aCSSSelector,
+    { type: "contextmenu", button: 2 },
+    gBrowser.selectedBrowser
+  );
+  await popupShownPromise;
+
+  let frameContextMenu = document.getElementById("frame");
+  popupShownPromise = BrowserTestUtils.waitForEvent(
+    frameContextMenu,
+    "popupshown"
+  );
+  frameContextMenu.openMenu(true);
+  await popupShownPromise;
+
+  return waitForViewSourceTab(async () => {
+    let popupHiddenPromise = BrowserTestUtils.waitForEvent(
+      frameContextMenu,
+      "popuphidden"
+    );
+    let item = document.getElementById("context-viewframesource");
+    frameContextMenu.menupopup.activateItem(item);
+    await popupHiddenPromise;
+  });
+}
+
+/**
+ * For a given view source tab, wait for the source loading step to
+ * complete.
+ */
+function waitForSourceLoaded(tab) {
+  return BrowserTestUtils.waitForContentEvent(
+    tab.linkedBrowser,
+    "pageshow",
+    false,
+    event => String(event.target.location).startsWith("view-source")
+  );
+}
+
+/**
+ * Open a new document in a new tab, select part of it, and view the source of
+ * that selection. The document is not closed afterwards.
+ *
+ * @param aURI - url to load
+ * @param aCSSSelector - used to specify a node to select. All of this node's
+ *                       children will be selected.
+ * @returns the new tab which shows the source.
+ */
+async function openDocumentSelect(aURI, aCSSSelector) {
+  let tab = await BrowserTestUtils.openNewForegroundTab(gBrowser, aURI);
+  registerCleanupFunction(function () {
+    gBrowser.removeTab(tab);
+  });
+
+  await SpecialPowers.spawn(
+    gBrowser.selectedBrowser,
+    [{ selector: aCSSSelector }],
+    async function (arg) {
+      let element = content.document.querySelector(arg.selector);
+      content.getSelection().selectAllChildren(element);
+    }
+  );
+
+  return openViewPartialSource(aCSSSelector);
+}
+
+/**
+ * Open a new document in a new tab and view the source of whole page.
+ * The document is not closed afterwards.
+ *
+ * @param aURI - url to load
+ * @returns the new tab which shows the source.
+ */
+async function openDocument(aURI) {
+  let tab = await BrowserTestUtils.openNewForegroundTab(gBrowser, aURI);
+  registerCleanupFunction(function () {
+    gBrowser.removeTab(tab);
+  });
+
+  return openViewSource();
+}
+
+function pushPrefs(...aPrefs) {
+  return SpecialPowers.pushPrefEnv({ set: aPrefs });
+}
+
+function waitForPrefChange(pref) {
+  let deferred = PromiseUtils.defer();
+  let observer = () => {
+    Preferences.ignore(pref, observer);
+    deferred.resolve();
+  };
+  Preferences.observe(pref, observer);
+  return deferred.promise;
+}
diff --git a/toolkit/components/viewsource/test/chrome.ini b/toolkit/components/viewsource/test/chrome.ini
new file mode 100644
index 0000000000..bd013ab6c9
--- /dev/null
+++ b/toolkit/components/viewsource/test/chrome.ini
@@ -0,0 +1,4 @@
+[DEFAULT]
+
+[test_bug428653.html]
+support-files = file_empty.html
diff --git a/toolkit/components/viewsource/test/file_empty.html b/toolkit/components/viewsource/test/file_empty.html
new file mode 100644
index 0000000000..495c23ec8a
--- /dev/null
+++ b/toolkit/components/viewsource/test/file_empty.html
@@ -0,0 +1 @@
+<!DOCTYPE html><html><body></body></html>
diff --git a/toolkit/components/viewsource/test/test_bug428653.html b/toolkit/components/viewsource/test/test_bug428653.html
new file mode 100644
index 0000000000..f800cb8f5f
--- /dev/null
+++ b/toolkit/components/viewsource/test/test_bug428653.html
@@ -0,0 +1,45 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=428653
+-->
+<head>
+  <title>View Source Test (bug 428653)</title>
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"/>
+</head>
+<body>
+
+  <iframe id="content" src="http://example.org/tests/toolkit/components/viewsource/test/file_empty.html"></iframe>
+
+  <script type="application/javascript">
+  /*
+  Test that we can't call the content browser's document.open() over Xrays.
+  See the security checks in nsHTMLDocument::Open, which make sure that the
+  entry global's principal matches that of the document.
+  */
+  SimpleTest.waitForExplicitFinish();
+
+  addLoadEvent(function testDocumentOpen() {
+    var browser = document.getElementById("content");
+    ok(browser, "got browser");
+    var doc = browser.contentDocument;
+    ok(doc, "got content document");
+
+    var opened = false;
+    try {
+      doc.open("text/html", "replace");
+      opened = true;
+    } catch (e) {
+      is(e.name, "SecurityError", "Unexpected exception");
+    }
+    is(opened, false, "Shouldn't have opened document");
+
+    doc.wrappedJSObject.open("text/html", "replace");
+    ok(true, "Should be able to open document via Xray Waiver");
+
+    SimpleTest.finish();
+  });
+  </script>
+</body>
+</html>