]> gitweb.stoutner.com Git - PrivacyBrowserAndroid.git/blobdiff - app/src/main/java/com/stoutner/privacybrowser/activities/MainWebViewActivity.java
Manually handle changes in screen layout. https://redmine.stoutner.com/issues/447
[PrivacyBrowserAndroid.git] / app / src / main / java / com / stoutner / privacybrowser / activities / MainWebViewActivity.java
index b6ba809717074ee392dee17ad0fc4dcdafe4ce9c..fbab8bfb37d977d82e659f28b4ab3fe100d60669 100644 (file)
@@ -279,6 +279,11 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
     // The swipe refresh layout top padding is used when exiting full screen browsing mode.  It is used in an inner class in `initializeWebView()`.
     private int swipeRefreshLayoutPaddingTop;
 
+    // The URL sanitizers are set in `applyAppSettings()` and used in `sanitizeUrl()`.
+    private boolean sanitizeGoogleAnalytics;
+    private boolean sanitizeFacebookClickIds;
+    private boolean sanitizeTwitterAmpRedirects;
+
     // The download strings are used in `onCreate()`, `onRequestPermissionResult()` and `initializeWebView()`.
     private String downloadUrl;
     private String downloadContentDisposition;
@@ -465,11 +470,10 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
 
         // Get handles for the navigation menu and the back and forward menu items.  The menu is zero-based.
         Menu navigationMenu = navigationView.getMenu();
-        MenuItem navigationCloseTabMenuItem = navigationMenu.getItem(0);
-        MenuItem navigationBackMenuItem = navigationMenu.getItem(3);
-        MenuItem navigationForwardMenuItem = navigationMenu.getItem(4);
-        MenuItem navigationHistoryMenuItem = navigationMenu.getItem(5);
-        MenuItem navigationRequestsMenuItem = navigationMenu.getItem(6);
+        MenuItem navigationBackMenuItem = navigationMenu.getItem(2);
+        MenuItem navigationForwardMenuItem = navigationMenu.getItem(3);
+        MenuItem navigationHistoryMenuItem = navigationMenu.getItem(4);
+        MenuItem navigationRequestsMenuItem = navigationMenu.getItem(5);
 
         // Initialize the web view pager adapter.
         webViewPagerAdapter = new WebViewPagerAdapter(getSupportFragmentManager());
@@ -500,7 +504,7 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                     // Create a handler to select the tab.
                     Handler selectTabHandler = new Handler();
 
-                    // Create a runnable select the new tab.
+                    // Create a runnable to select the tab.
                     Runnable selectTabRunnable = () -> {
                         // Get a handle for the tab.
                         TabLayout.Tab tab = tabLayout.getTabAt(position);
@@ -512,8 +516,8 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                         tab.select();
                     };
 
-                    // Select the tab layout after 100 milliseconds, which leaves enough time for a new tab to be created.
-                    selectTabHandler.postDelayed(selectTabRunnable, 100);
+                    // Select the tab layout after 150 milliseconds, which leaves enough time for a new tab to be inflated.
+                    selectTabHandler.postDelayed(selectTabRunnable, 150);
                 }
             }
 
@@ -766,7 +770,6 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                     }
 
                     // Update the navigation menu items.
-                    navigationCloseTabMenuItem.setEnabled(tabLayout.getTabCount() > 1);
                     navigationBackMenuItem.setEnabled(currentWebView.canGoBack());
                     navigationForwardMenuItem.setEnabled(currentWebView.canGoForward());
                     navigationHistoryMenuItem.setEnabled((currentWebView.canGoBack() || currentWebView.canGoForward()));
@@ -810,28 +813,19 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
         String intentAction = intent.getAction();
         Uri intentUriData = intent.getData();
 
-        // Only process the URI if it contains data.  If the user pressed the desktop icon after the app was already running the URI will be null.
-        if (intentUriData != null) {
-            // Sets the new intent as the activity intent, which replaces the one that originally started the app.
-            setIntent(intent);
+        // Determine if this is a web search.
+        boolean isWebSearch = ((intentAction != null) && intentAction.equals(Intent.ACTION_WEB_SEARCH));
 
+        // Only process the URI if it contains data or it is a web search.  If the user pressed the desktop icon after the app was already running the URI will be null.
+        if (intentUriData != null || isWebSearch) {
             // Get the shared preferences.
             SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
 
-            // Add a new tab if specified in the preferences.
-            if (sharedPreferences.getBoolean("open_intents_in_new_tab", true)) {
-                // Set the loading new intent flag.
-                loadingNewIntent = true;
-
-                // Add a new tab.
-                addTab(null);
-            }
-
             // Create a URL string.
             String url;
 
             // If the intent action is a web search, perform the search.
-            if ((intentAction != null) && intentAction.equals(Intent.ACTION_WEB_SEARCH)) {
+            if (isWebSearch) {
                 // Create an encoded URL string.
                 String encodedUrlString;
 
@@ -849,8 +843,17 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                 url = intentUriData.toString();
             }
 
-            // Load the URL.
-            loadUrl(url);
+            // Add a new tab if specified in the preferences.
+            if (sharedPreferences.getBoolean("open_intents_in_new_tab", true)) {  // Load the URL in a new tab.
+                // Set the loading new intent flag.
+                loadingNewIntent = true;
+
+                // Add a new tab.
+                addNewTab(url);
+            } else {  // Load the URL in the current tab.
+                // Make it so.
+                loadUrl(url);
+            }
 
             // Get a handle for the drawer layout.
             DrawerLayout drawerLayout = findViewById(R.id.drawerlayout);
@@ -864,9 +867,6 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
             if (drawerLayout.isDrawerVisible(GravityCompat.END)) {
                 drawerLayout.closeDrawer(GravityCompat.END);
             }
-
-            // Clear the keyboard if displayed and remove the focus on the urlTextBar if it has it.
-            currentWebView.requestFocus();
         }
     }
 
@@ -1144,6 +1144,7 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
         MenuItem blockAllThirdPartyRequestsMenuItem = menu.findItem(R.id.block_all_third_party_requests);
         MenuItem fontSizeMenuItem = menu.findItem(R.id.font_size);
         MenuItem swipeToRefreshMenuItem = menu.findItem(R.id.swipe_to_refresh);
+        MenuItem wideViewportMenuItem = menu.findItem(R.id.wide_viewport);
         MenuItem displayImagesMenuItem = menu.findItem(R.id.display_images);
         MenuItem nightModeMenuItem = menu.findItem(R.id.night_mode);
         MenuItem proxyThroughOrbotMenuItem = menu.findItem(R.id.proxy_through_orbot);
@@ -1180,6 +1181,7 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
             ultraPrivacyMenuItem.setChecked(currentWebView.isBlocklistEnabled(NestedScrollWebView.ULTRA_PRIVACY));
             blockAllThirdPartyRequestsMenuItem.setChecked(currentWebView.isBlocklistEnabled(NestedScrollWebView.THIRD_PARTY_REQUESTS));
             swipeToRefreshMenuItem.setChecked(currentWebView.getSwipeToRefresh());
+            wideViewportMenuItem.setChecked(currentWebView.getSettings().getUseWideViewPort());
             displayImagesMenuItem.setChecked(currentWebView.getSettings().getLoadsImagesAutomatically());
             nightModeMenuItem.setChecked(currentWebView.getNightMode());
 
@@ -1898,19 +1900,19 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
 
                 // Update the swipe refresh layout.
                 if (currentWebView.getSwipeToRefresh()) {  // Swipe to refresh is enabled.
-                    if (Build.VERSION.SDK_INT >= 23) {  // For API >= 23, the status of the scroll refresh listener is continuously updated by the on scroll change listener.
-                        // Only enable the swipe refresh layout if the WebView is scrolled to the top.
-                        swipeRefreshLayout.setEnabled(currentWebView.getY() == 0);
-                    } else {  // For API < 23, the swipe refresh layout is always enabled.
-                        // Enable the swipe refresh layout.
-                        swipeRefreshLayout.setEnabled(true);
-                    }
+                    // Only enable the swipe refresh layout if the WebView is scrolled to the top.  It is updated every time the scroll changes.
+                    swipeRefreshLayout.setEnabled(currentWebView.getY() == 0);
                 } else {  // Swipe to refresh is disabled.
                     // Disable the swipe refresh layout.
                     swipeRefreshLayout.setEnabled(false);
                 }
                 return true;
 
+            case R.id.wide_viewport:
+                // Toggle the viewport.
+                currentWebView.getSettings().setUseWideViewPort(!currentWebView.getSettings().getUseWideViewPort());
+                return true;
+
             case R.id.display_images:
                 if (currentWebView.getSettings().getLoadsImagesAutomatically()) {  // Images are currently loaded automatically.
                     // Disable loading of images.
@@ -1979,6 +1981,29 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                 }, 200);
                 return true;
 
+            case R.id.print:
+                // Get a print manager instance.
+                PrintManager printManager = (PrintManager) getSystemService(Context.PRINT_SERVICE);
+
+                // Remove the lint error below that print manager might be null.
+                assert printManager != null;
+
+                // Create a print document adapter from the current WebView.
+                PrintDocumentAdapter printDocumentAdapter = currentWebView.createPrintDocumentAdapter();
+
+                // Print the document.
+                printManager.print(getString(R.string.privacy_browser_web_page), printDocumentAdapter, null);
+                return true;
+
+            case R.id.add_to_homescreen:
+                // Instantiate the create home screen shortcut dialog.
+                DialogFragment createHomeScreenShortcutDialogFragment = CreateHomeScreenShortcutDialog.createDialog(currentWebView.getTitle(), currentWebView.getUrl(),
+                        currentWebView.getFavoriteOrDefaultIcon());
+
+                // Show the create home screen shortcut dialog.
+                createHomeScreenShortcutDialogFragment.show(getSupportFragmentManager(), getString(R.string.create_shortcut));
+                return true;
+
             case R.id.view_source:
                 // Create an intent to launch the view source activity.
                 Intent viewSourceIntent = new Intent(this, ViewSourceActivity.class);
@@ -2004,20 +2029,6 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                 startActivity(Intent.createChooser(shareIntent, getString(R.string.share_url)));
                 return true;
 
-            case R.id.print:
-                // Get a print manager instance.
-                PrintManager printManager = (PrintManager) getSystemService(Context.PRINT_SERVICE);
-
-                // Remove the lint error below that print manager might be null.
-                assert printManager != null;
-
-                // Create a print document adapter from the current WebView.
-                PrintDocumentAdapter printDocumentAdapter = currentWebView.createPrintDocumentAdapter();
-
-                // Print the document.
-                printManager.print(getString(R.string.privacy_browser_web_page), printDocumentAdapter, null);
-                return true;
-
             case R.id.open_with_app:
                 openWithApp(currentWebView.getUrl());
                 return true;
@@ -2026,15 +2037,6 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                 openWithBrowser(currentWebView.getUrl());
                 return true;
 
-            case R.id.add_to_homescreen:
-                // Instantiate the create home screen shortcut dialog.
-                DialogFragment createHomeScreenShortcutDialogFragment = CreateHomeScreenShortcutDialog.createDialog(currentWebView.getTitle(), currentWebView.getUrl(),
-                        currentWebView.getFavoriteOrDefaultIcon());
-
-                // Show the create home screen shortcut dialog.
-                createHomeScreenShortcutDialogFragment.show(getSupportFragmentManager(), getString(R.string.create_shortcut));
-                return true;
-
             case R.id.proxy_through_orbot:
                 // Toggle the proxy through Orbot variable.
                 proxyThroughOrbot = !proxyThroughOrbot;
@@ -2076,183 +2078,9 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
 
         // Run the commands that correspond to the selected menu item.
         switch (menuItemId) {
-            case R.id.close_tab:
-                // Close the current tab.
-                closeCurrentTab();
-                break;
-
             case R.id.clear_and_exit:
-                // Close the bookmarks cursor and database.
-                bookmarksCursor.close();
-                bookmarksDatabaseHelper.close();
-
-                // Get the status of the clear everything preference.
-                boolean clearEverything = sharedPreferences.getBoolean("clear_everything", true);
-
-                // Get a handle for the runtime.
-                Runtime runtime = Runtime.getRuntime();
-
-                // Get the application's private data directory, which will be something like `/data/user/0/com.stoutner.privacybrowser.standard`,
-                // which links to `/data/data/com.stoutner.privacybrowser.standard`.
-                String privateDataDirectoryString = getApplicationInfo().dataDir;
-
-                // Clear cookies.
-                if (clearEverything || sharedPreferences.getBoolean("clear_cookies", true)) {
-                    // The command to remove cookies changed slightly in API 21.
-                    if (Build.VERSION.SDK_INT >= 21) {
-                        CookieManager.getInstance().removeAllCookies(null);
-                    } else {
-                        CookieManager.getInstance().removeAllCookie();
-                    }
-
-                    // Manually delete the cookies database, as `CookieManager` sometimes will not flush its changes to disk before `System.exit(0)` is run.
-                    try {
-                        // Two commands must be used because `Runtime.exec()` does not like `*`.
-                        Process deleteCookiesProcess = runtime.exec("rm -f " + privateDataDirectoryString + "/app_webview/Cookies");
-                        Process deleteCookiesJournalProcess = runtime.exec("rm -f " + privateDataDirectoryString + "/app_webview/Cookies-journal");
-
-                        // Wait until the processes have finished.
-                        deleteCookiesProcess.waitFor();
-                        deleteCookiesJournalProcess.waitFor();
-                    } catch (Exception exception) {
-                        // Do nothing if an error is thrown.
-                    }
-                }
-
-                // Clear DOM storage.
-                if (clearEverything || sharedPreferences.getBoolean("clear_dom_storage", true)) {
-                    // Ask `WebStorage` to clear the DOM storage.
-                    WebStorage webStorage = WebStorage.getInstance();
-                    webStorage.deleteAllData();
-
-                    // Manually delete the DOM storage files and directories, as `WebStorage` sometimes will not flush its changes to disk before `System.exit(0)` is run.
-                    try {
-                        // A `String[]` must be used because the directory contains a space and `Runtime.exec` will otherwise not escape the string correctly.
-                        Process deleteLocalStorageProcess = runtime.exec(new String[] {"rm", "-rf", privateDataDirectoryString + "/app_webview/Local Storage/"});
-
-                        // Multiple commands must be used because `Runtime.exec()` does not like `*`.
-                        Process deleteIndexProcess = runtime.exec("rm -rf " + privateDataDirectoryString + "/app_webview/IndexedDB");
-                        Process deleteQuotaManagerProcess = runtime.exec("rm -f " + privateDataDirectoryString + "/app_webview/QuotaManager");
-                        Process deleteQuotaManagerJournalProcess = runtime.exec("rm -f " + privateDataDirectoryString + "/app_webview/QuotaManager-journal");
-                        Process deleteDatabaseProcess = runtime.exec("rm -rf " + privateDataDirectoryString + "/app_webview/databases");
-
-                        // Wait until the processes have finished.
-                        deleteLocalStorageProcess.waitFor();
-                        deleteIndexProcess.waitFor();
-                        deleteQuotaManagerProcess.waitFor();
-                        deleteQuotaManagerJournalProcess.waitFor();
-                        deleteDatabaseProcess.waitFor();
-                    } catch (Exception exception) {
-                        // Do nothing if an error is thrown.
-                    }
-                }
-
-                // Clear form data if the API < 26.
-                if ((Build.VERSION.SDK_INT < 26) && (clearEverything || sharedPreferences.getBoolean("clear_form_data", true))) {
-                    WebViewDatabase webViewDatabase = WebViewDatabase.getInstance(this);
-                    webViewDatabase.clearFormData();
-
-                    // Manually delete the form data database, as `WebViewDatabase` sometimes will not flush its changes to disk before `System.exit(0)` is run.
-                    try {
-                        // A string array must be used because the database contains a space and `Runtime.exec` will not otherwise escape the string correctly.
-                        Process deleteWebDataProcess = runtime.exec(new String[] {"rm", "-f", privateDataDirectoryString + "/app_webview/Web Data"});
-                        Process deleteWebDataJournalProcess = runtime.exec(new String[] {"rm", "-f", privateDataDirectoryString + "/app_webview/Web Data-journal"});
-
-                        // Wait until the processes have finished.
-                        deleteWebDataProcess.waitFor();
-                        deleteWebDataJournalProcess.waitFor();
-                    } catch (Exception exception) {
-                        // Do nothing if an error is thrown.
-                    }
-                }
-
-                // Clear the cache.
-                if (clearEverything || sharedPreferences.getBoolean("clear_cache", true)) {
-                    // Clear the cache from each WebView.
-                    for (int i = 0; i < webViewPagerAdapter.getCount(); i++) {
-                        // Get the WebView tab fragment.
-                        WebViewTabFragment webViewTabFragment = webViewPagerAdapter.getPageFragment(i);
-
-                        // Get the fragment view.
-                        View fragmentView = webViewTabFragment.getView();
-
-                        // Only clear the cache if the WebView exists.
-                        if (fragmentView != null) {
-                            // Get the nested scroll WebView from the tab fragment.
-                            NestedScrollWebView nestedScrollWebView = fragmentView.findViewById(R.id.nestedscroll_webview);
-
-                            // Clear the cache for this WebView.
-                            nestedScrollWebView.clearCache(true);
-                        }
-                    }
-
-                    // Manually delete the cache directories.
-                    try {
-                        // Delete the main cache directory.
-                        Process deleteCacheProcess = runtime.exec("rm -rf " + privateDataDirectoryString + "/cache");
-
-                        // Delete the secondary `Service Worker` cache directory.
-                        // A string array must be used because the directory contains a space and `Runtime.exec` will otherwise not escape the string correctly.
-                        Process deleteServiceWorkerProcess = runtime.exec(new String[] {"rm", "-rf", privateDataDirectoryString + "/app_webview/Service Worker/"});
-
-                        // Wait until the processes have finished.
-                        deleteCacheProcess.waitFor();
-                        deleteServiceWorkerProcess.waitFor();
-                    } catch (Exception exception) {
-                        // Do nothing if an error is thrown.
-                    }
-                }
-
-                // Wipe out each WebView.
-                for (int i = 0; i < webViewPagerAdapter.getCount(); i++) {
-                    // Get the WebView tab fragment.
-                    WebViewTabFragment webViewTabFragment = webViewPagerAdapter.getPageFragment(i);
-
-                    // Get the fragment view.
-                    View fragmentView = webViewTabFragment.getView();
-
-                    // Only wipe out the WebView if it exists.
-                    if (fragmentView != null) {
-                        // Get the nested scroll WebView from the tab fragment.
-                        NestedScrollWebView nestedScrollWebView = fragmentView.findViewById(R.id.nestedscroll_webview);
-
-                        // Clear SSL certificate preferences for this WebView.
-                        nestedScrollWebView.clearSslPreferences();
-
-                        // Clear the back/forward history for this WebView.
-                        nestedScrollWebView.clearHistory();
-
-                        // Destroy the internal state of `mainWebView`.
-                        nestedScrollWebView.destroy();
-                    }
-                }
-
-                // Clear the custom headers.
-                customHeaders.clear();
-
-                // Manually delete the `app_webview` folder, which contains the cookies, DOM storage, form data, and `Service Worker` cache.
-                // See `https://code.google.com/p/android/issues/detail?id=233826&thanks=233826&ts=1486670530`.
-                if (clearEverything) {
-                    try {
-                        // Delete the folder.
-                        Process deleteAppWebviewProcess = runtime.exec("rm -rf " + privateDataDirectoryString + "/app_webview");
-
-                        // Wait until the process has finished.
-                        deleteAppWebviewProcess.waitFor();
-                    } catch (Exception exception) {
-                        // Do nothing if an error is thrown.
-                    }
-                }
-
-                // Close Privacy Browser.  `finishAndRemoveTask` also removes Privacy Browser from the recent app list.
-                if (Build.VERSION.SDK_INT >= 21) {
-                    finishAndRemoveTask();
-                } else {
-                    finish();
-                }
-
-                // Remove the terminated program from RAM.  The status code is `0`.
-                System.exit(0);
+                // Clear and exit Privacy Browser.
+                clearAndExit();
                 break;
 
             case R.id.home:
@@ -2488,13 +2316,10 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                 // Set the target URL as the title of the `ContextMenu`.
                 menu.setHeaderTitle(linkUrl);
 
-                // Add a Load URL entry.
+                // Add an Open in New Tab entry.
                 menu.add(R.string.open_in_new_tab).setOnMenuItemClickListener((MenuItem item) -> {
-                    // Add a new tab.
-                    addTab(null);
-
-                    // Load the URL.
-                    loadUrl(linkUrl);
+                    // Load the link URL in a new tab.
+                    addNewTab(linkUrl);
                     return false;
                 });
 
@@ -2596,89 +2421,23 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                 menu.add(R.string.cancel);
                 break;
 
-            // `IMAGE_TYPE` is an image.
+            // `IMAGE_TYPE` is an image. `SRC_IMAGE_ANCHOR_TYPE` is an image that is also a link.  Privacy Browser processes them the same.
             case WebView.HitTestResult.IMAGE_TYPE:
+            case WebView.HitTestResult.SRC_IMAGE_ANCHOR_TYPE:
                 // Get the image URL.
                 imageUrl = hitTestResult.getExtra();
 
-                // Set the image URL as the title of the `ContextMenu`.
+                // Set the image URL as the title of the context menu.
                 menu.setHeaderTitle(imageUrl);
 
-                // Add a View Image entry.
-                menu.add(R.string.view_image).setOnMenuItemClickListener(item -> {
-                    loadUrl(imageUrl);
-                    return false;
-                });
-
-                // Add a Download Image entry.
-                menu.add(R.string.download_image).setOnMenuItemClickListener((MenuItem item) -> {
-                    // Check if the download should be processed by an external app.
-                    if (sharedPreferences.getBoolean("download_with_external_app", false)) {  // Download with an external app.
-                        openUrlWithExternalApp(imageUrl);
-                    } else {  // Download with Android's download manager.
-                        // Check to see if the storage permission has already been granted.
-                        if (ContextCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_DENIED) {  // The storage permission needs to be requested.
-                            // Store the image URL for use by `onRequestPermissionResult()`.
-                            downloadImageUrl = imageUrl;
-
-                            // Show a dialog if the user has previously denied the permission.
-                            if (ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.WRITE_EXTERNAL_STORAGE)) {  // Show a dialog explaining the request first.
-                                // Instantiate the download location permission alert dialog and set the download type to DOWNLOAD_IMAGE.
-                                DialogFragment downloadLocationPermissionDialogFragment = DownloadLocationPermissionDialog.downloadType(DownloadLocationPermissionDialog.DOWNLOAD_IMAGE);
-
-                                // Show the download location permission alert dialog.  The permission will be requested when the dialog is closed.
-                                downloadLocationPermissionDialogFragment.show(fragmentManager, getString(R.string.download_location));
-                            } else {  // Show the permission request directly.
-                                // Request the permission.  The download dialog will be launched by `onRequestPermissionResult().
-                                ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, DOWNLOAD_IMAGE_REQUEST_CODE);
-                            }
-                        } else {  // The storage permission has already been granted.
-                            // Get a handle for the download image alert dialog.
-                            DialogFragment downloadImageDialogFragment = DownloadImageDialog.imageUrl(imageUrl);
-
-                            // Show the download image alert dialog.
-                            downloadImageDialogFragment.show(fragmentManager, getString(R.string.download));
-                        }
-                    }
-                    return false;
-                });
-
-                // Add a Copy URL entry.
-                menu.add(R.string.copy_url).setOnMenuItemClickListener(item -> {
-                    // Save the image URL in a `ClipData`.
-                    ClipData srcImageTypeClipData = ClipData.newPlainText(getString(R.string.url), imageUrl);
-
-                    // Set the `ClipData` as the clipboard's primary clip.
-                    clipboardManager.setPrimaryClip(srcImageTypeClipData);
-                    return false;
-                });
-
-                // Add an Open with App entry.
-                menu.add(R.string.open_with_app).setOnMenuItemClickListener((MenuItem item) -> {
-                    openWithApp(imageUrl);
-                    return false;
-                });
-
-                // Add an Open with Browser entry.
-                menu.add(R.string.open_with_browser).setOnMenuItemClickListener((MenuItem item) -> {
-                    openWithBrowser(imageUrl);
+                // Add an Open in New Tab entry.
+                menu.add(R.string.open_in_new_tab).setOnMenuItemClickListener((MenuItem item) -> {
+                    // Load the image URL in a new tab.
+                    addNewTab(imageUrl);
                     return false;
                 });
 
-                // Add a `Cancel` entry, which by default closes the `ContextMenu`.
-                menu.add(R.string.cancel);
-                break;
-
-
-            // `SRC_IMAGE_ANCHOR_TYPE` is an image that is also a link.
-            case WebView.HitTestResult.SRC_IMAGE_ANCHOR_TYPE:
-                // Get the image URL.
-                imageUrl = hitTestResult.getExtra();
-
-                // Set the image URL as the title of the `ContextMenu`.
-                menu.setHeaderTitle(imageUrl);
-
-                // Add a `View Image` entry.
+                // Add a View Image entry.
                 menu.add(R.string.view_image).setOnMenuItemClickListener(item -> {
                     loadUrl(imageUrl);
                     return false;
@@ -3160,6 +2919,9 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
         } else {  // There isn't anything to do in Privacy Browser.
             // Run the default commands.
             super.onBackPressed();
+
+            // Manually kill Privacy Browser.  Otherwise, it is glitchy when restarted.
+            System.exit(0);
         }
     }
 
@@ -3244,6 +3006,9 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
     }
 
     private void loadUrl(String url) {
+        // Sanitize the URL.
+        url = sanitizeUrl(url);
+
         // Apply the domain settings.
         applyDomainSettings(currentWebView, url, true, false);
 
@@ -3298,6 +3063,9 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
         // Store the values from the shared preferences in variables.
         incognitoModeEnabled = sharedPreferences.getBoolean("incognito_mode", false);
         boolean doNotTrackEnabled = sharedPreferences.getBoolean("do_not_track", false);
+        sanitizeGoogleAnalytics = sharedPreferences.getBoolean("google_analytics", true);
+        sanitizeFacebookClickIds = sharedPreferences.getBoolean("facebook_click_ids", true);
+        sanitizeTwitterAmpRedirects = sharedPreferences.getBoolean("twitter_amp_redirects", true);
         proxyThroughOrbot = sharedPreferences.getBoolean("proxy_through_orbot", false);
         fullScreenBrowsingModeEnabled = sharedPreferences.getBoolean("full_screen_browsing_mode", false);
         hideAppBar = sharedPreferences.getBoolean("hide_app_bar", true);
@@ -3448,8 +3216,8 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
             newHostName = "";
         }
 
-        // Only apply the domain settings if a new domain is being loaded.  This allows the user to set temporary settings for JavaScript, cookies, DOM storage, etc.
-        if (!nestedScrollWebView.getCurrentDomainName().equals(newHostName)) {
+        // Apply the domain settings if a new domain is being loaded or if the new domain is blank.  This allows the user to set temporary settings for JavaScript, cookies, DOM storage, etc.
+        if (!nestedScrollWebView.getCurrentDomainName().equals(newHostName) || newHostName.equals("")) {
             // Set the new host name as the current domain name.
             nestedScrollWebView.setCurrentDomainName(newHostName);
 
@@ -3555,8 +3323,9 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
             String defaultFontSizeString = sharedPreferences.getString("font_size", getString(R.string.font_size_default_value));
             String defaultUserAgentName = sharedPreferences.getString("user_agent", getString(R.string.user_agent_default_value));
             boolean defaultSwipeToRefresh = sharedPreferences.getBoolean("swipe_to_refresh", true);
-            boolean displayWebpageImages = sharedPreferences.getBoolean("display_webpage_images", true);
             boolean darkTheme = sharedPreferences.getBoolean("dark_theme", false);
+            boolean wideViewport = sharedPreferences.getBoolean("wide_viewport", true);
+            boolean displayWebpageImages = sharedPreferences.getBoolean("display_webpage_images", true);
 
             // Get a handle for the cookie manager.
             CookieManager cookieManager = CookieManager.getInstance();
@@ -3598,6 +3367,7 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                 int fontSize = currentDomainSettingsCursor.getInt(currentDomainSettingsCursor.getColumnIndex(DomainsDatabaseHelper.FONT_SIZE));
                 int swipeToRefreshInt = currentDomainSettingsCursor.getInt(currentDomainSettingsCursor.getColumnIndex(DomainsDatabaseHelper.SWIPE_TO_REFRESH));
                 int nightModeInt = currentDomainSettingsCursor.getInt(currentDomainSettingsCursor.getColumnIndex(DomainsDatabaseHelper.NIGHT_MODE));
+                int wideViewportInt = currentDomainSettingsCursor.getInt(currentDomainSettingsCursor.getColumnIndex(DomainsDatabaseHelper.WIDE_VIEWPORT));
                 int displayWebpageImagesInt = currentDomainSettingsCursor.getInt(currentDomainSettingsCursor.getColumnIndex(DomainsDatabaseHelper.DISPLAY_IMAGES));
                 boolean pinnedSslCertificate = (currentDomainSettingsCursor.getInt(currentDomainSettingsCursor.getColumnIndex(DomainsDatabaseHelper.PINNED_SSL_CERTIFICATE)) == 1);
                 String pinnedSslIssuedToCName = currentDomainSettingsCursor.getString(currentDomainSettingsCursor.getColumnIndex(DomainsDatabaseHelper.SSL_ISSUED_TO_COMMON_NAME));
@@ -3640,17 +3410,17 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
 
                 // Set night mode according to the night mode int.
                 switch (nightModeInt) {
-                    case DomainsDatabaseHelper.NIGHT_MODE_SYSTEM_DEFAULT:
+                    case DomainsDatabaseHelper.SYSTEM_DEFAULT:
                         // Set night mode according to the current default.
                         nestedScrollWebView.setNightMode(sharedPreferences.getBoolean("night_mode", false));
                         break;
 
-                    case DomainsDatabaseHelper.NIGHT_MODE_ENABLED:
+                    case DomainsDatabaseHelper.ENABLED:
                         // Enable night mode.
                         nestedScrollWebView.setNightMode(true);
                         break;
 
-                    case DomainsDatabaseHelper.NIGHT_MODE_DISABLED:
+                    case DomainsDatabaseHelper.DISABLED:
                         // Disable night mode.
                         nestedScrollWebView.setNightMode(false);
                         break;
@@ -3688,59 +3458,55 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                     nestedScrollWebView.getSettings().setTextZoom(fontSize);
                 }
 
-                // Only set the user agent if the webpage is not currently loading.  Otherwise, changing the user agent on redirects can cause the original website to reload.
-                // <https://redmine.stoutner.com/issues/160>
-                if (nestedScrollWebView.getProgress() == 100) {  // A URL is not loading.
-                    // Set the user agent.
-                    if (userAgentName.equals(getString(R.string.system_default_user_agent))) {  // Use the system default user agent.
-                        // Get the array position of the default user agent name.
-                        int defaultUserAgentArrayPosition = userAgentNamesArray.getPosition(defaultUserAgentName);
-
-                        // Set the user agent according to the system default.
-                        switch (defaultUserAgentArrayPosition) {
-                            case UNRECOGNIZED_USER_AGENT:  // The default user agent name is not on the canonical list.
-                                // This is probably because it was set in an older version of Privacy Browser before the switch to persistent user agent names.
-                                nestedScrollWebView.getSettings().setUserAgentString(defaultUserAgentName);
-                                break;
-
-                            case SETTINGS_WEBVIEW_DEFAULT_USER_AGENT:
-                                // Set the user agent to `""`, which uses the default value.
-                                nestedScrollWebView.getSettings().setUserAgentString("");
-                                break;
-
-                            case SETTINGS_CUSTOM_USER_AGENT:
-                                // Set the default custom user agent.
-                                nestedScrollWebView.getSettings().setUserAgentString(sharedPreferences.getString("custom_user_agent", getString(R.string.custom_user_agent_default_value)));
-                                break;
-
-                            default:
-                                // Get the user agent string from the user agent data array
-                                nestedScrollWebView.getSettings().setUserAgentString(userAgentDataArray[defaultUserAgentArrayPosition]);
-                        }
-                    } else {  // Set the user agent according to the stored name.
-                        // Get the array position of the user agent name.
-                        int userAgentArrayPosition = userAgentNamesArray.getPosition(userAgentName);
-
-                        switch (userAgentArrayPosition) {
-                            case UNRECOGNIZED_USER_AGENT:  // The user agent name contains a custom user agent.
-                                nestedScrollWebView.getSettings().setUserAgentString(userAgentName);
-                                break;
-
-                            case SETTINGS_WEBVIEW_DEFAULT_USER_AGENT:
-                                // Set the user agent to `""`, which uses the default value.
-                                nestedScrollWebView.getSettings().setUserAgentString("");
-                                break;
-
-                            default:
-                                // Get the user agent string from the user agent data array.
-                                nestedScrollWebView.getSettings().setUserAgentString(userAgentDataArray[userAgentArrayPosition]);
-                        }
+                // Set the user agent.
+                if (userAgentName.equals(getString(R.string.system_default_user_agent))) {  // Use the system default user agent.
+                    // Get the array position of the default user agent name.
+                    int defaultUserAgentArrayPosition = userAgentNamesArray.getPosition(defaultUserAgentName);
+
+                    // Set the user agent according to the system default.
+                    switch (defaultUserAgentArrayPosition) {
+                        case UNRECOGNIZED_USER_AGENT:  // The default user agent name is not on the canonical list.
+                            // This is probably because it was set in an older version of Privacy Browser before the switch to persistent user agent names.
+                            nestedScrollWebView.getSettings().setUserAgentString(defaultUserAgentName);
+                            break;
+
+                        case SETTINGS_WEBVIEW_DEFAULT_USER_AGENT:
+                            // Set the user agent to `""`, which uses the default value.
+                            nestedScrollWebView.getSettings().setUserAgentString("");
+                            break;
+
+                        case SETTINGS_CUSTOM_USER_AGENT:
+                            // Set the default custom user agent.
+                            nestedScrollWebView.getSettings().setUserAgentString(sharedPreferences.getString("custom_user_agent", getString(R.string.custom_user_agent_default_value)));
+                            break;
+
+                        default:
+                            // Get the user agent string from the user agent data array
+                            nestedScrollWebView.getSettings().setUserAgentString(userAgentDataArray[defaultUserAgentArrayPosition]);
+                    }
+                } else {  // Set the user agent according to the stored name.
+                    // Get the array position of the user agent name.
+                    int userAgentArrayPosition = userAgentNamesArray.getPosition(userAgentName);
+
+                    switch (userAgentArrayPosition) {
+                        case UNRECOGNIZED_USER_AGENT:  // The user agent name contains a custom user agent.
+                            nestedScrollWebView.getSettings().setUserAgentString(userAgentName);
+                            break;
+
+                        case SETTINGS_WEBVIEW_DEFAULT_USER_AGENT:
+                            // Set the user agent to `""`, which uses the default value.
+                            nestedScrollWebView.getSettings().setUserAgentString("");
+                            break;
+
+                        default:
+                            // Get the user agent string from the user agent data array.
+                            nestedScrollWebView.getSettings().setUserAgentString(userAgentDataArray[userAgentArrayPosition]);
                     }
                 }
 
                 // Set swipe to refresh.
                 switch (swipeToRefreshInt) {
-                    case DomainsDatabaseHelper.SWIPE_TO_REFRESH_SYSTEM_DEFAULT:
+                    case DomainsDatabaseHelper.SYSTEM_DEFAULT:
                         // Store the swipe to refresh status in the nested scroll WebView.
                         nestedScrollWebView.setSwipeToRefresh(defaultSwipeToRefresh);
 
@@ -3748,7 +3514,7 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                         swipeRefreshLayout.setEnabled(defaultSwipeToRefresh);
                         break;
 
-                    case DomainsDatabaseHelper.SWIPE_TO_REFRESH_ENABLED:
+                    case DomainsDatabaseHelper.ENABLED:
                         // Store the swipe to refresh status in the nested scroll WebView.
                         nestedScrollWebView.setSwipeToRefresh(true);
 
@@ -3756,7 +3522,7 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                         swipeRefreshLayout.setEnabled(true);
                         break;
 
-                    case DomainsDatabaseHelper.SWIPE_TO_REFRESH_DISABLED:
+                    case DomainsDatabaseHelper.DISABLED:
                         // Store the swipe to refresh status in the nested scroll WebView.
                         nestedScrollWebView.setSwipeToRefresh(false);
 
@@ -3764,17 +3530,32 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                         swipeRefreshLayout.setEnabled(false);
                 }
 
+                // Set the viewport.
+                switch (wideViewportInt) {
+                    case DomainsDatabaseHelper.SYSTEM_DEFAULT:
+                        nestedScrollWebView.getSettings().setUseWideViewPort(wideViewport);
+                        break;
+
+                    case DomainsDatabaseHelper.ENABLED:
+                        nestedScrollWebView.getSettings().setUseWideViewPort(true);
+                        break;
+
+                    case DomainsDatabaseHelper.DISABLED:
+                        nestedScrollWebView.getSettings().setUseWideViewPort(false);
+                        break;
+                }
+
                 // Set the loading of webpage images.
                 switch (displayWebpageImagesInt) {
-                    case DomainsDatabaseHelper.DISPLAY_WEBPAGE_IMAGES_SYSTEM_DEFAULT:
+                    case DomainsDatabaseHelper.SYSTEM_DEFAULT:
                         nestedScrollWebView.getSettings().setLoadsImagesAutomatically(displayWebpageImages);
                         break;
 
-                    case DomainsDatabaseHelper.DISPLAY_WEBPAGE_IMAGES_ENABLED:
+                    case DomainsDatabaseHelper.ENABLED:
                         nestedScrollWebView.getSettings().setLoadsImagesAutomatically(true);
                         break;
 
-                    case DomainsDatabaseHelper.DISPLAY_WEBPAGE_IMAGES_DISABLED:
+                    case DomainsDatabaseHelper.DISABLED:
                         nestedScrollWebView.getSettings().setLoadsImagesAutomatically(false);
                         break;
                 }
@@ -3832,35 +3613,34 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                     cookieManager.setAcceptThirdPartyCookies(nestedScrollWebView, defaultThirdPartyCookiesEnabled);
                 }
 
-                // Only set the user agent if the webpage is not currently loading.  Otherwise, changing the user agent on redirects can cause the original website to reload.
-                // <https://redmine.stoutner.com/issues/160>
-                if (nestedScrollWebView.getProgress() == 100) {  // A URL is not loading.
-                    // Get the array position of the user agent name.
-                    int userAgentArrayPosition = userAgentNamesArray.getPosition(defaultUserAgentName);
+                // Get the array position of the user agent name.
+                int userAgentArrayPosition = userAgentNamesArray.getPosition(defaultUserAgentName);
 
-                    // Set the user agent.
-                    switch (userAgentArrayPosition) {
-                        case UNRECOGNIZED_USER_AGENT:  // The default user agent name is not on the canonical list.
-                            // This is probably because it was set in an older version of Privacy Browser before the switch to persistent user agent names.
-                            nestedScrollWebView.getSettings().setUserAgentString(defaultUserAgentName);
-                            break;
+                // Set the user agent.
+                switch (userAgentArrayPosition) {
+                    case UNRECOGNIZED_USER_AGENT:  // The default user agent name is not on the canonical list.
+                        // This is probably because it was set in an older version of Privacy Browser before the switch to persistent user agent names.
+                        nestedScrollWebView.getSettings().setUserAgentString(defaultUserAgentName);
+                        break;
 
-                        case SETTINGS_WEBVIEW_DEFAULT_USER_AGENT:
-                            // Set the user agent to `""`, which uses the default value.
-                            nestedScrollWebView.getSettings().setUserAgentString("");
-                            break;
+                    case SETTINGS_WEBVIEW_DEFAULT_USER_AGENT:
+                        // Set the user agent to `""`, which uses the default value.
+                        nestedScrollWebView.getSettings().setUserAgentString("");
+                        break;
 
-                        case SETTINGS_CUSTOM_USER_AGENT:
-                            // Set the default custom user agent.
-                            nestedScrollWebView.getSettings().setUserAgentString(sharedPreferences.getString("custom_user_agent", getString(R.string.custom_user_agent_default_value)));
-                            break;
+                    case SETTINGS_CUSTOM_USER_AGENT:
+                        // Set the default custom user agent.
+                        nestedScrollWebView.getSettings().setUserAgentString(sharedPreferences.getString("custom_user_agent", getString(R.string.custom_user_agent_default_value)));
+                        break;
 
-                        default:
-                            // Get the user agent string from the user agent data array
-                            nestedScrollWebView.getSettings().setUserAgentString(userAgentDataArray[userAgentArrayPosition]);
-                    }
+                    default:
+                        // Get the user agent string from the user agent data array
+                        nestedScrollWebView.getSettings().setUserAgentString(userAgentDataArray[userAgentArrayPosition]);
                 }
 
+                // Set the viewport.
+                nestedScrollWebView.getSettings().setUseWideViewPort(wideViewport);
+
                 // Set the loading of webpage images.
                 nestedScrollWebView.getSettings().setLoadsImagesAutomatically(displayWebpageImages);
 
@@ -4204,7 +3984,54 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
         startActivity(openWithBrowserIntent);
     }
 
+    private String sanitizeUrl(String url) {
+        // Sanitize Google Analytics.
+        if (sanitizeGoogleAnalytics) {
+            // Remove `?utm_`.
+            if (url.contains("?utm_")) {
+                url = url.substring(0, url.indexOf("?utm_"));
+            }
+
+            // Remove `&utm_`.
+            if (url.contains("&utm_")) {
+                url = url.substring(0, url.indexOf("&utm_"));
+            }
+        }
+
+        // Sanitize Facebook Click IDs.
+        if (sanitizeFacebookClickIds) {
+            // Remove `?fbclid=`.
+            if (url.contains("?fbclid=")) {
+                url = url.substring(0, url.indexOf("?fbclid="));
+            }
+
+            // Remove `&fbclid=`.
+            if (url.contains("&fbclid=")) {
+                url = url.substring(0, url.indexOf("&fbclid="));
+            }
+        }
+
+        // Sanitize Twitter AMP redirects.
+        if (sanitizeTwitterAmpRedirects) {
+            // Remove `?amp=1`.
+            if (url.contains("?amp=1")) {
+                url = url.substring(0, url.indexOf("?amp=1"));
+            }
+        }
+
+        // Return the sanitized URL.
+        return url;
+    }
+
     public void addTab(View view) {
+        // Add a new tab with a blank URL.
+        addNewTab("");
+    }
+
+    private void addNewTab(String url) {
+        // Sanitize the URL.
+        url = sanitizeUrl(url);
+
         // Get a handle for the tab layout and the view pager.
         TabLayout tabLayout = findViewById(R.id.tablayout);
         ViewPager webViewPager = findViewById(R.id.webviewpager);
@@ -4225,7 +4052,20 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
         newTab.setCustomView(R.layout.tab_custom_view);
 
         // Add the new WebView page.
-        webViewPagerAdapter.addPage(newTabNumber, webViewPager);
+        webViewPagerAdapter.addPage(newTabNumber, webViewPager, url);
+    }
+
+    public void closeTab(View view) {
+        // Get a handle for the tab layout.
+        TabLayout tabLayout = findViewById(R.id.tablayout);
+
+        // Run the command according to the number of tabs.
+        if (tabLayout.getTabCount() > 1) {  // There is more than one tab open.
+            // Close the current tab.
+            closeCurrentTab();
+        } else {  // There is only one tab open.
+            clearAndExit();
+        }
     }
 
     private void closeCurrentTab() {
@@ -4249,6 +4089,183 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
         appBarLayout.setExpanded(true);
     }
 
+    private void clearAndExit() {
+        // Get a handle for the shared preferences.
+        SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
+
+        // Close the bookmarks cursor and database.
+        bookmarksCursor.close();
+        bookmarksDatabaseHelper.close();
+
+        // Get the status of the clear everything preference.
+        boolean clearEverything = sharedPreferences.getBoolean("clear_everything", true);
+
+        // Get a handle for the runtime.
+        Runtime runtime = Runtime.getRuntime();
+
+        // Get the application's private data directory, which will be something like `/data/user/0/com.stoutner.privacybrowser.standard`,
+        // which links to `/data/data/com.stoutner.privacybrowser.standard`.
+        String privateDataDirectoryString = getApplicationInfo().dataDir;
+
+        // Clear cookies.
+        if (clearEverything || sharedPreferences.getBoolean("clear_cookies", true)) {
+            // The command to remove cookies changed slightly in API 21.
+            if (Build.VERSION.SDK_INT >= 21) {
+                CookieManager.getInstance().removeAllCookies(null);
+            } else {
+                CookieManager.getInstance().removeAllCookie();
+            }
+
+            // Manually delete the cookies database, as `CookieManager` sometimes will not flush its changes to disk before `System.exit(0)` is run.
+            try {
+                // Two commands must be used because `Runtime.exec()` does not like `*`.
+                Process deleteCookiesProcess = runtime.exec("rm -f " + privateDataDirectoryString + "/app_webview/Cookies");
+                Process deleteCookiesJournalProcess = runtime.exec("rm -f " + privateDataDirectoryString + "/app_webview/Cookies-journal");
+
+                // Wait until the processes have finished.
+                deleteCookiesProcess.waitFor();
+                deleteCookiesJournalProcess.waitFor();
+            } catch (Exception exception) {
+                // Do nothing if an error is thrown.
+            }
+        }
+
+        // Clear DOM storage.
+        if (clearEverything || sharedPreferences.getBoolean("clear_dom_storage", true)) {
+            // Ask `WebStorage` to clear the DOM storage.
+            WebStorage webStorage = WebStorage.getInstance();
+            webStorage.deleteAllData();
+
+            // Manually delete the DOM storage files and directories, as `WebStorage` sometimes will not flush its changes to disk before `System.exit(0)` is run.
+            try {
+                // A `String[]` must be used because the directory contains a space and `Runtime.exec` will otherwise not escape the string correctly.
+                Process deleteLocalStorageProcess = runtime.exec(new String[] {"rm", "-rf", privateDataDirectoryString + "/app_webview/Local Storage/"});
+
+                // Multiple commands must be used because `Runtime.exec()` does not like `*`.
+                Process deleteIndexProcess = runtime.exec("rm -rf " + privateDataDirectoryString + "/app_webview/IndexedDB");
+                Process deleteQuotaManagerProcess = runtime.exec("rm -f " + privateDataDirectoryString + "/app_webview/QuotaManager");
+                Process deleteQuotaManagerJournalProcess = runtime.exec("rm -f " + privateDataDirectoryString + "/app_webview/QuotaManager-journal");
+                Process deleteDatabaseProcess = runtime.exec("rm -rf " + privateDataDirectoryString + "/app_webview/databases");
+
+                // Wait until the processes have finished.
+                deleteLocalStorageProcess.waitFor();
+                deleteIndexProcess.waitFor();
+                deleteQuotaManagerProcess.waitFor();
+                deleteQuotaManagerJournalProcess.waitFor();
+                deleteDatabaseProcess.waitFor();
+            } catch (Exception exception) {
+                // Do nothing if an error is thrown.
+            }
+        }
+
+        // Clear form data if the API < 26.
+        if ((Build.VERSION.SDK_INT < 26) && (clearEverything || sharedPreferences.getBoolean("clear_form_data", true))) {
+            WebViewDatabase webViewDatabase = WebViewDatabase.getInstance(this);
+            webViewDatabase.clearFormData();
+
+            // Manually delete the form data database, as `WebViewDatabase` sometimes will not flush its changes to disk before `System.exit(0)` is run.
+            try {
+                // A string array must be used because the database contains a space and `Runtime.exec` will not otherwise escape the string correctly.
+                Process deleteWebDataProcess = runtime.exec(new String[] {"rm", "-f", privateDataDirectoryString + "/app_webview/Web Data"});
+                Process deleteWebDataJournalProcess = runtime.exec(new String[] {"rm", "-f", privateDataDirectoryString + "/app_webview/Web Data-journal"});
+
+                // Wait until the processes have finished.
+                deleteWebDataProcess.waitFor();
+                deleteWebDataJournalProcess.waitFor();
+            } catch (Exception exception) {
+                // Do nothing if an error is thrown.
+            }
+        }
+
+        // Clear the cache.
+        if (clearEverything || sharedPreferences.getBoolean("clear_cache", true)) {
+            // Clear the cache from each WebView.
+            for (int i = 0; i < webViewPagerAdapter.getCount(); i++) {
+                // Get the WebView tab fragment.
+                WebViewTabFragment webViewTabFragment = webViewPagerAdapter.getPageFragment(i);
+
+                // Get the fragment view.
+                View fragmentView = webViewTabFragment.getView();
+
+                // Only clear the cache if the WebView exists.
+                if (fragmentView != null) {
+                    // Get the nested scroll WebView from the tab fragment.
+                    NestedScrollWebView nestedScrollWebView = fragmentView.findViewById(R.id.nestedscroll_webview);
+
+                    // Clear the cache for this WebView.
+                    nestedScrollWebView.clearCache(true);
+                }
+            }
+
+            // Manually delete the cache directories.
+            try {
+                // Delete the main cache directory.
+                Process deleteCacheProcess = runtime.exec("rm -rf " + privateDataDirectoryString + "/cache");
+
+                // Delete the secondary `Service Worker` cache directory.
+                // A string array must be used because the directory contains a space and `Runtime.exec` will otherwise not escape the string correctly.
+                Process deleteServiceWorkerProcess = runtime.exec(new String[] {"rm", "-rf", privateDataDirectoryString + "/app_webview/Service Worker/"});
+
+                // Wait until the processes have finished.
+                deleteCacheProcess.waitFor();
+                deleteServiceWorkerProcess.waitFor();
+            } catch (Exception exception) {
+                // Do nothing if an error is thrown.
+            }
+        }
+
+        // Wipe out each WebView.
+        for (int i = 0; i < webViewPagerAdapter.getCount(); i++) {
+            // Get the WebView tab fragment.
+            WebViewTabFragment webViewTabFragment = webViewPagerAdapter.getPageFragment(i);
+
+            // Get the fragment view.
+            View fragmentView = webViewTabFragment.getView();
+
+            // Only wipe out the WebView if it exists.
+            if (fragmentView != null) {
+                // Get the nested scroll WebView from the tab fragment.
+                NestedScrollWebView nestedScrollWebView = fragmentView.findViewById(R.id.nestedscroll_webview);
+
+                // Clear SSL certificate preferences for this WebView.
+                nestedScrollWebView.clearSslPreferences();
+
+                // Clear the back/forward history for this WebView.
+                nestedScrollWebView.clearHistory();
+
+                // Destroy the internal state of `mainWebView`.
+                nestedScrollWebView.destroy();
+            }
+        }
+
+        // Clear the custom headers.
+        customHeaders.clear();
+
+        // Manually delete the `app_webview` folder, which contains the cookies, DOM storage, form data, and `Service Worker` cache.
+        // See `https://code.google.com/p/android/issues/detail?id=233826&thanks=233826&ts=1486670530`.
+        if (clearEverything) {
+            try {
+                // Delete the folder.
+                Process deleteAppWebviewProcess = runtime.exec("rm -rf " + privateDataDirectoryString + "/app_webview");
+
+                // Wait until the process has finished.
+                deleteAppWebviewProcess.waitFor();
+            } catch (Exception exception) {
+                // Do nothing if an error is thrown.
+            }
+        }
+
+        // Close Privacy Browser.  `finishAndRemoveTask` also removes Privacy Browser from the recent app list.
+        if (Build.VERSION.SDK_INT >= 21) {
+            finishAndRemoveTask();
+        } else {
+            finish();
+        }
+
+        // Remove the terminated program from RAM.  The status code is `0`.
+        System.exit(0);
+    }
+
     private void setCurrentWebView(int pageNumber) {
         // Get a handle for the shared preferences.
         SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
@@ -4261,7 +4278,7 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
         EditText urlEditText = findViewById(R.id.url_edittext);
         SwipeRefreshLayout swipeRefreshLayout = findViewById(R.id.swiperefreshlayout);
 
-        //Stop the swipe to refresh indicator if it is running
+        // Stop the swipe to refresh indicator if it is running
         swipeRefreshLayout.setRefreshing(false);
 
         // Get the WebView tab fragment.
@@ -4271,19 +4288,14 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
         View fragmentView = webViewTabFragment.getView();
 
         // Set the current WebView if the fragment view is not null.
-        if (fragmentView != null) {
+        if (fragmentView != null) {  // The fragment has been populated.
             // Store the current WebView.
             currentWebView = fragmentView.findViewById(R.id.nestedscroll_webview);
 
             // Update the status of swipe to refresh.
             if (currentWebView.getSwipeToRefresh()) {  // Swipe to refresh is enabled.
-                if (Build.VERSION.SDK_INT >= 23) {  // For API >= 23, swipe refresh layout is continuously updated with an on scroll change listener and only enabled if the WebView is scrolled to the top.
-                    // Enable the swipe refresh layout if the WebView is scrolled all the way to the top.
-                    swipeRefreshLayout.setEnabled(currentWebView.getY() == 0);
-                } else {
-                    // Enable the swipe refresh layout.
-                    swipeRefreshLayout.setEnabled(true);
-                }
+                // Enable the swipe refresh layout if the WebView is scrolled all the way to the top.  It is updated every time the scroll changes.
+                swipeRefreshLayout.setEnabled(currentWebView.getY() == 0);
             } else {  // Swipe to refresh is disabled.
                 // Disable the swipe refresh layout.
                 swipeRefreshLayout.setEnabled(false);
@@ -4347,11 +4359,23 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
             } else {
                 urlRelativeLayout.setBackground(getResources().getDrawable(R.color.transparent));
             }
+        } else {  // The fragment has not been populated.  Try again in 100 milliseconds.
+            // Create a handler to set the current WebView.
+            Handler setCurrentWebViewHandler = new Handler();
+
+            // Create a runnable to set the current WebView.
+            Runnable setCurrentWebWebRunnable = () -> {
+                // Set the current WebView.
+                setCurrentWebView(pageNumber);
+            };
+
+            // Try setting the current WebView again after 100 milliseconds.
+            setCurrentWebViewHandler.postDelayed(setCurrentWebWebRunnable, 100);
         }
     }
 
     @Override
-    public void initializeWebView(NestedScrollWebView nestedScrollWebView, int pageNumber, ProgressBar progressBar) {
+    public void initializeWebView(NestedScrollWebView nestedScrollWebView, int pageNumber, ProgressBar progressBar, String url) {
         // Get handles for the activity views.
         FrameLayout rootFrameLayout = findViewById(R.id.root_framelayout);
         DrawerLayout drawerLayout = findViewById(R.id.drawerlayout);
@@ -4400,9 +4424,6 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
             nestedScrollWebView.getSettings().setMixedContentMode(WebSettings.MIXED_CONTENT_NEVER_ALLOW);
         }
 
-        // Set the WebView to use a wide viewport.  Otherwise, some web pages will be scrunched and some content will render outside the screen.
-        nestedScrollWebView.getSettings().setUseWideViewPort(true);
-
         // Set the WebView to load in overview mode (zoomed out to the maximum width).
         nestedScrollWebView.getSettings().setLoadWithOverviewMode(true);
 
@@ -4504,14 +4525,14 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
         registerForContextMenu(nestedScrollWebView);
 
         // Allow the downloading of files.
-        nestedScrollWebView.setDownloadListener((String url, String userAgent, String contentDisposition, String mimetype, long contentLength) -> {
+        nestedScrollWebView.setDownloadListener((String downloadUrl, String userAgent, String contentDisposition, String mimetype, long contentLength) -> {
             // Check if the download should be processed by an external app.
             if (downloadWithExternalApp) {  // Download with an external app.
                 // Create a download intent.  Not specifying the action type will display the maximum number of options.
                 Intent downloadIntent = new Intent();
 
                 // Set the URI and the MIME type.  Specifying `text/html` displays a good number of options.
-                downloadIntent.setDataAndType(Uri.parse(url), "text/html");
+                downloadIntent.setDataAndType(Uri.parse(downloadUrl), "text/html");
 
                 // Flag the intent to open in a new task.
                 downloadIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
@@ -4524,7 +4545,7 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                     // The WRITE_EXTERNAL_STORAGE permission needs to be requested.
 
                     // Store the variables for future use by `onRequestPermissionsResult()`.
-                    downloadUrl = url;
+                    this.downloadUrl = downloadUrl;
                     downloadContentDisposition = contentDisposition;
                     downloadContentLength = contentLength;
 
@@ -4541,7 +4562,7 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                     }
                 } else {  // The storage permission has already been granted.
                     // Get a handle for the download file alert dialog.
-                    DialogFragment downloadFileDialogFragment = DownloadFileDialog.fromUrl(url, contentDisposition, contentLength);
+                    DialogFragment downloadFileDialogFragment = DownloadFileDialog.fromUrl(downloadUrl, contentDisposition, contentLength);
 
                     // Show the download file alert dialog.
                     downloadFileDialogFragment.show(getSupportFragmentManager(), getString(R.string.download));
@@ -4683,8 +4704,14 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                     // Get the title text view from the tab.
                     TextView tabTitleTextView = tabView.findViewById(R.id.title_textview);
 
-                    // Set the title as the tab text.
-                    tabTitleTextView.setText(title);
+                    // Set the title according to the URL.
+                    if (title.equals("about:blank")) {
+                        // Set the title to indicate a new tab.
+                        tabTitleTextView.setText(R.string.new_tab);
+                    } else {
+                        // Set the title as the tab text.
+                        tabTitleTextView.setText(title);
+                    }
                 }
             }
 
@@ -4820,6 +4847,9 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
             // The deprecated `shouldOverrideUrlLoading` must be used until API >= 24.
             @Override
             public boolean shouldOverrideUrlLoading(WebView view, String url) {
+                // Sanitize the url.
+                url = sanitizeUrl(url);
+
                 if (url.startsWith("http")) {  // Load the URL in Privacy Browser.
                     // Apply the domain settings for the new URL.  This doesn't do anything if the domain has not changed.
                     boolean userAgentChanged = applyDomainSettings(nestedScrollWebView, url, true, false);
@@ -4893,6 +4923,9 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
             // Check requests against the block lists.  The deprecated `shouldInterceptRequest()` must be used until minimum API >= 21.
             @Override
             public WebResourceResponse shouldInterceptRequest(WebView view, String url) {
+                // Sanitize the URL.
+                url = sanitizeUrl(url);
+
                 // Get a handle for the navigation view.
                 NavigationView navigationView = findViewById(R.id.navigationview);
 
@@ -4900,7 +4933,7 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                 Menu navigationMenu = navigationView.getMenu();
 
                 // Get a handle for the navigation requests menu item.  The menu is 0 based.
-                MenuItem navigationRequestsMenuItem = navigationMenu.getItem(6);
+                MenuItem navigationRequestsMenuItem = navigationMenu.getItem(5);
 
                 // Create an empty web resource response to be used if the resource request is blocked.
                 WebResourceResponse emptyWebResourceResponse = new WebResourceResponse("text/plain", "utf8", new ByteArrayInputStream("".getBytes()));
@@ -5280,7 +5313,7 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                         }
                     }
 
-                    // Replace Refresh with Stop if the options menu has been created.  (The WebView typically begins loading before the menu items are instantiated.)
+                    // Replace Refresh with Stop if the options menu has been created.  (The first WebView typically begins loading before the menu items are instantiated.)
                     if (optionsMenu != null) {
                         // Get a handle for the refresh menu item.
                         MenuItem refreshMenuItem = optionsMenu.findItem(R.id.refresh);
@@ -5305,12 +5338,6 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
 
             @Override
             public void onPageFinished(WebView view, String url) {
-                // Reset the wide view port if it has been turned off by the waiting for Orbot message.
-                if (!waitingForOrbot) {
-                    // Only use a wide view port if the URL starts with `http`, not for `file://` and `content://`.
-                    nestedScrollWebView.getSettings().setUseWideViewPort(url.startsWith("http"));
-                }
-
                 // Flush any cookies to persistent storage.  The cookie manager has become very lazy about flushing cookies in recent versions.
                 if (nestedScrollWebView.getAcceptFirstPartyCookies() && Build.VERSION.SDK_INT >= 21) {
                     CookieManager.getInstance().flush();
@@ -5374,10 +5401,18 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                         CheckPinnedMismatchHelper.checkPinnedMismatch(getSupportFragmentManager(), nestedScrollWebView);
                     }
 
+                    // Get the current URL from the nested scroll WebView.  This is more accurate than using the URL passed into the method, which is sometimes not the final one.
+                    String currentUrl = nestedScrollWebView.getUrl();
+
+                    // Get the current tab.
+                    TabLayout.Tab tab = tabLayout.getTabAt(currentPagePosition);
+
                     // Update the URL text bar if the page is currently selected and the user is not currently typing in the URL edit text.
-                    if ((tabLayout.getSelectedTabPosition() == currentPagePosition) && !urlEditText.hasFocus()) {
+                    // Crash records show that, in some crazy way, it is possible for the current URL to be blank at this point.
+                    // Probably some sort of race condition when Privacy Browser is being resumed.
+                    if ((tabLayout.getSelectedTabPosition() == currentPagePosition) && !urlEditText.hasFocus() && (currentUrl != null)) {
                         // Check to see if the URL is `about:blank`.
-                        if (nestedScrollWebView.getUrl().equals("about:blank")) {  // The WebView is blank.
+                        if (currentUrl.equals("about:blank")) {  // The WebView is blank.
                             // Display the hint in the URL edit text.
                             urlEditText.setText("");
 
@@ -5387,36 +5422,45 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                             // Display the keyboard.
                             inputMethodManager.showSoftInput(urlEditText, 0);
 
-                            // Hide the WebView, which causes the default background color to be displayed according to the theme.
-                            nestedScrollWebView.setVisibility(View.INVISIBLE);
-
                             // Apply the domain settings.  This clears any settings from the previous domain.
                             applyDomainSettings(nestedScrollWebView, "", true, false);
+
+                            // Only populate the title text view if the tab has been fully created.
+                            if (tab != null) {
+                                // Get the custom view from the tab.
+                                View tabView = tab.getCustomView();
+
+                                // Remove the incorrect warning below that the current tab view might be null.
+                                assert tabView != null;
+
+                                // Get the title text view from the tab.
+                                TextView tabTitleTextView = tabView.findViewById(R.id.title_textview);
+
+                                // Set the title as the tab text.
+                                tabTitleTextView.setText(R.string.new_tab);
+                            }
                         } else {  // The WebView has loaded a webpage.
                             // Display the final URL.  Getting the URL from the WebView instead of using the one provided by `onPageFinished()` makes websites like YouTube function correctly.
-                            urlEditText.setText(nestedScrollWebView.getUrl());
+                            urlEditText.setText(currentUrl);
 
                             // Apply text highlighting to the URL.
                             highlightUrlText();
-                        }
-                    }
-
-                    // Get the current tab.
-                    TabLayout.Tab tab = tabLayout.getTabAt(currentPagePosition);
 
-                    // Only populate the title text view if the tab has been fully created.
-                    if (tab != null) {
-                        // Get the custom view from the tab.
-                        View tabView = tab.getCustomView();
+                            // Only populate the title text view if the tab has been fully created.
+                            if (tab != null) {
+                                // Get the custom view from the tab.
+                                View tabView = tab.getCustomView();
 
-                        // Remove the incorrect warning below that the current tab view might be null.
-                        assert tabView != null;
+                                // Remove the incorrect warning below that the current tab view might be null.
+                                assert tabView != null;
 
-                        // Get the title text view from the tab.
-                        TextView tabTitleTextView = tabView.findViewById(R.id.title_textview);
+                                // Get the title text view from the tab.
+                                TextView tabTitleTextView = tabView.findViewById(R.id.title_textview);
 
-                        // Set the title as the tab text.  Sometimes `onReceivedTitle()` is not called, especially when navigating history.
-                        tabTitleTextView.setText(nestedScrollWebView.getTitle());
+                                // Set the title as the tab text.  Sometimes `onReceivedTitle()` is not called, especially when navigating history.
+                                tabTitleTextView.setText(nestedScrollWebView.getTitle());
+                            }
+                        }
                     }
                 }
             }
@@ -5513,6 +5557,30 @@ public class MainWebViewActivity extends AppCompatActivity implements CreateBook
                     }
                 }
             }
+        } else {  // This is not the first tab.
+            // Apply the domain settings.
+            applyDomainSettings(nestedScrollWebView, url, false, false);
+
+            // Load the URL.
+            nestedScrollWebView.loadUrl(url, customHeaders);
+
+            // Set the focus and display the keyboard if the URL is blank.
+            if (url.equals("")) {
+                // Request focus for the URL text box.
+                urlEditText.requestFocus();
+
+                // Create a display keyboard handler.
+                Handler displayKeyboardHandler = new Handler();
+
+                // Create a display keyboard runnable.
+                Runnable displayKeyboardRunnable = () -> {
+                    // Display the keyboard.
+                    inputMethodManager.showSoftInput(urlEditText, 0);
+                };
+
+                // Display the keyboard after 100 milliseconds, which leaves enough time for the tab to transition.
+                displayKeyboardHandler.postDelayed(displayKeyboardRunnable, 100);
+            }
         }
     }
 }
\ No newline at end of file