Fork uMatrix

Pretty much just changing the name and the copyright.

1 files changed, 3466 insertions, 0 deletions

diff --git a/js/vapi-background.js b/js/vapi-background.js
new file mode 100644
index 0000000..b4f1eac
--- /dev/null
+++ b/js/vapi-background.js
@@ -0,0 +1,3466 @@
+/*******************************************************************************
+
+    ηMatrix - a browser extension to black/white list requests.
+    Copyright (C) 2014-2019 The uMatrix/uBlock Origin authors
+    Copyright (C) 2019 Alessio Vanni
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see {http://www.gnu.org/licenses/}.
+
+    uMatrix Home: https://github.com/gorhill/uMatrix
+*/
+
+/* jshint bitwise: false, esnext: true */
+/* global self, Components, punycode */
+
+// For background page
+
+'use strict';
+
+/******************************************************************************/
+
+(function() {
+
+/******************************************************************************/
+
+// Useful links
+//
+// https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XPCOM/Reference/Interface
+// https://developer.mozilla.org/en-US/docs/Mozilla/JavaScript_code_modules/Services.jsm
+
+/******************************************************************************/
+
+const {classes: Cc, interfaces: Ci, utils: Cu} = Components;
+const {Services} = Cu.import('resource://gre/modules/Services.jsm', null);
+
+/******************************************************************************/
+
+var vAPI = self.vAPI = self.vAPI || {};
+vAPI.firefox = true;
+vAPI.modernFirefox = Services.appinfo.ID === '{ec8030f7-c20a-464f-9b0e-13a3a9e97384}' &&
+                     Services.vc.compare(Services.appinfo.platformVersion, '44') > 0;
+
+/******************************************************************************/
+
+var deferUntil = function(testFn, mainFn, details) {
+    if ( typeof details !== 'object' ) {
+        details = {};
+    }
+
+    var now = 0;
+    var next = details.next || 200;
+    var until = details.until || 2000;
+
+    var check = function() {
+        if ( testFn() === true || now >= until ) {
+            mainFn();
+            return;
+        }
+        now += next;
+        vAPI.setTimeout(check, next);
+    };
+
+    if ( 'sync' in details && details.sync === true ) {
+        check();
+    } else {
+        vAPI.setTimeout(check, 1);
+    }
+};
+
+/******************************************************************************/
+
+vAPI.app = {
+    name: 'uMatrix',
+    version: location.hash.slice(1)
+};
+
+/******************************************************************************/
+
+vAPI.app.start = function() {
+};
+
+/******************************************************************************/
+
+vAPI.app.stop = function() {
+};
+
+/******************************************************************************/
+
+vAPI.app.restart = function() {
+    // Listening in bootstrap.js
+    Cc['@mozilla.org/childprocessmessagemanager;1']
+        .getService(Ci.nsIMessageSender)
+        .sendAsyncMessage(location.host + '-restart');
+};
+
+/******************************************************************************/
+
+// List of things that needs to be destroyed when disabling the extension
+// Only functions should be added to it
+
+var cleanupTasks = [];
+
+// This must be updated manually, every time a new task is added/removed
+
+// Fixed by github.com/AlexVallat:
+//   https://github.com/AlexVallat/uBlock/commit/7b781248f00cbe3d61b1cc367c440db80fa06049
+//   7 instances of cleanupTasks.push, but one is unique to fennec, and one to desktop.
+var expectedNumberOfCleanups = 7;
+
+window.addEventListener('unload', function() {
+    if ( typeof vAPI.app.onShutdown === 'function' ) {
+        vAPI.app.onShutdown();
+    }
+
+    // IMPORTANT: cleanup tasks must be executed using LIFO order.
+    var i = cleanupTasks.length;
+    while ( i-- ) {
+        cleanupTasks[i]();
+    }
+
+    if ( cleanupTasks.length < expectedNumberOfCleanups ) {
+        console.error(
+            'uMatrix> Cleanup tasks performed: %s (out of %s)',
+            cleanupTasks.length,
+            expectedNumberOfCleanups
+        );
+    }
+
+    // frameModule needs to be cleared too
+    var frameModuleURL = vAPI.getURL('frameModule.js');
+    var frameModule = {};
+    Cu.import(frameModuleURL, frameModule);
+    frameModule.contentObserver.unregister();
+    Cu.unload(frameModuleURL);
+});
+
+/******************************************************************************/
+
+// For now, only booleans.
+
+vAPI.browserSettings = {
+    originalValues: {},
+
+    rememberOriginalValue: function(path, setting) {
+        var key = path + '.' + setting;
+        if ( this.originalValues.hasOwnProperty(key) ) {
+            return;
+        }
+        var hasUserValue;
+        var branch = Services.prefs.getBranch(path + '.');
+        try {
+            hasUserValue = branch.prefHasUserValue(setting);
+        } catch (ex) {
+        }
+        if ( hasUserValue !== undefined ) {
+            this.originalValues[key] = hasUserValue ? this.getValue(path, setting) : undefined;
+        }
+    },
+
+    clear: function(path, setting) {
+        var key = path + '.' + setting;
+
+        // Value was not overriden -- nothing to restore
+        if ( this.originalValues.hasOwnProperty(key) === false ) {
+            return;
+        }
+
+        var value = this.originalValues[key];
+        // https://github.com/gorhill/uBlock/issues/292#issuecomment-109621979
+        // Forget the value immediately, it may change outside of
+        // uBlock control.
+        delete this.originalValues[key];
+
+        // Original value was a default one
+        if ( value === undefined ) {
+            try {
+                Services.prefs.getBranch(path + '.').clearUserPref(setting);
+            } catch (ex) {
+            }
+            return;
+        }
+
+        // Reset to original value
+        this.setValue(path, setting, value);
+    },
+
+    getValue: function(path, setting) {
+        var branch = Services.prefs.getBranch(path + '.');
+        var getMethod;
+
+        // https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XPCOM/Reference/Interface/nsIPrefBranch#getPrefType%28%29
+        switch ( branch.getPrefType(setting) ) {
+        case  64: // PREF_INT
+            getMethod = 'getIntPref';
+            break;
+        case 128: // PREF_BOOL
+            getMethod = 'getBoolPref';
+            break;
+        default:  // not supported
+            return;
+        }
+
+        try {
+            return branch[getMethod](setting);
+        } catch (ex) {
+        }
+    },
+
+    setValue: function(path, setting, value) {
+        var setMethod;
+        switch ( typeof value ) {
+        case  'number':
+            setMethod = 'setIntPref';
+            break;
+        case 'boolean':
+            setMethod = 'setBoolPref';
+            break;
+        default:  // not supported
+            return;
+        }
+
+        try {
+            Services.prefs.getBranch(path + '.')[setMethod](setting, value);
+        } catch (ex) {
+        }
+    },
+
+    setSetting: function(setting, value) {
+        var prefName, prefVal;
+        switch ( setting ) {
+        case 'prefetching':
+            this.rememberOriginalValue('network', 'prefetch-next');
+            // http://betanews.com/2015/08/15/firefox-stealthily-loads-webpages-when-you-hover-over-links-heres-how-to-stop-it/
+            // https://bugzilla.mozilla.org/show_bug.cgi?id=814169
+            // Sigh.
+            this.rememberOriginalValue('network.http', 'speculative-parallel-limit');
+            // https://github.com/gorhill/uBlock/issues/292
+            // "true" means "do not disable", i.e. leave entry alone
+            if ( value ) {
+                this.clear('network', 'prefetch-next');
+                this.clear('network.http', 'speculative-parallel-limit');
+            } else {
+                this.setValue('network', 'prefetch-next', false);
+                this.setValue('network.http', 'speculative-parallel-limit', 0);
+            }
+            break;
+
+        case 'hyperlinkAuditing':
+            this.rememberOriginalValue('browser', 'send_pings');
+            this.rememberOriginalValue('beacon', 'enabled');
+            // https://github.com/gorhill/uBlock/issues/292
+            // "true" means "do not disable", i.e. leave entry alone
+            if ( value ) {
+                this.clear('browser', 'send_pings');
+                this.clear('beacon', 'enabled');
+            } else {
+                this.setValue('browser', 'send_pings', false);
+                this.setValue('beacon', 'enabled', false);
+            }
+            break;
+
+        // https://github.com/gorhill/uBlock/issues/894
+        // Do not disable completely WebRTC if it can be avoided. FF42+
+        // has a `media.peerconnection.ice.default_address_only` pref which
+        // purpose is to prevent local IP address leakage.
+        case 'webrtcIPAddress':
+            if ( this.getValue('media.peerconnection', 'ice.default_address_only') !== undefined ) {
+                prefName = 'ice.default_address_only';
+                prefVal = true;
+            } else {
+                prefName = 'enabled';
+                prefVal = false;
+            }
+
+            this.rememberOriginalValue('media.peerconnection', prefName);
+            if ( value ) {
+                this.clear('media.peerconnection', prefName);
+            } else {
+                this.setValue('media.peerconnection', prefName, prefVal);
+            }
+            break;
+
+        default:
+            break;
+        }
+    },
+
+    set: function(details) {
+        for ( var setting in details ) {
+            if ( details.hasOwnProperty(setting) === false ) {
+                continue;
+            }
+            this.setSetting(setting, !!details[setting]);
+        }
+    },
+
+    restoreAll: function() {
+        var pos;
+        for ( var key in this.originalValues ) {
+            if ( this.originalValues.hasOwnProperty(key) === false ) {
+                continue;
+            }
+            pos = key.lastIndexOf('.');
+            this.clear(key.slice(0, pos), key.slice(pos + 1));
+        }
+    }
+};
+
+cleanupTasks.push(vAPI.browserSettings.restoreAll.bind(vAPI.browserSettings));
+
+/******************************************************************************/
+
+// API matches that of chrome.storage.local:
+//   https://developer.chrome.com/extensions/storage
+
+vAPI.storage = (function() {
+    var db = null;
+    var vacuumTimer = null;
+
+    var close = function() {
+        if ( vacuumTimer !== null ) {
+            clearTimeout(vacuumTimer);
+            vacuumTimer = null;
+        }
+        if ( db === null ) {
+            return;
+        }
+        db.asyncClose();
+        db = null;
+    };
+
+    var open = function() {
+        if ( db !== null ) {
+            return db;
+        }
+
+        // Create path
+        var path = Services.dirsvc.get('ProfD', Ci.nsIFile);
+        path.append('extension-data');
+        if ( !path.exists() ) {
+            path.create(Ci.nsIFile.DIRECTORY_TYPE, parseInt('0774', 8));
+        }
+        if ( !path.isDirectory() ) {
+            throw Error('Should be a directory...');
+        }
+        path.append(location.host + '.sqlite');
+
+        // Open database
+        try {
+            db = Services.storage.openDatabase(path);
+            if ( db.connectionReady === false ) {
+                db.asyncClose();
+                db = null;
+            }
+        } catch (ex) {
+        }
+
+        if ( db === null ) {
+            return null;
+        }
+
+        // Database was opened, register cleanup task
+        cleanupTasks.push(close);
+
+        // Setup database
+        db.createAsyncStatement('CREATE TABLE IF NOT EXISTS "settings" ("name" TEXT PRIMARY KEY NOT NULL, "value" TEXT);')
+          .executeAsync();
+
+        if ( vacuum !== null ) {
+            vacuumTimer = vAPI.setTimeout(vacuum, 60000);
+        }
+
+        return db;
+    };
+
+    // https://developer.mozilla.org/en-US/docs/Storage/Performance#Vacuuming_and_zero-fill
+    // Vacuum only once, and only while idle
+    var vacuum = function() {
+        vacuumTimer = null;
+        if ( db === null ) {
+            return;
+        }
+        var idleSvc = Cc['@mozilla.org/widget/idleservice;1']
+                       .getService(Ci.nsIIdleService);
+        if ( idleSvc.idleTime < 60000 ) {
+            vacuumTimer = vAPI.setTimeout(vacuum, 60000);
+            return;
+        }
+        db.createAsyncStatement('VACUUM').executeAsync();
+        vacuum = null;
+    };
+
+    // Execute a query
+    var runStatement = function(stmt, callback) {
+        var result = {};
+
+        stmt.executeAsync({
+            handleResult: function(rows) {
+                if ( !rows || typeof callback !== 'function' ) {
+                    return;
+                }
+
+                var row;
+
+                while ( (row = rows.getNextRow()) ) {
+                    // we assume that there will be two columns, since we're
+                    // using it only for preferences
+                    result[row.getResultByIndex(0)] = row.getResultByIndex(1);
+                }
+            },
+            handleCompletion: function(reason) {
+                if ( typeof callback === 'function' && reason === 0 ) {
+                    callback(result);
+                }
+            },
+            handleError: function(error) {
+                console.error('SQLite error ', error.result, error.message);
+                // Caller expects an answer regardless of failure.
+                if ( typeof callback === 'function' ) {
+                    callback(null);
+                }
+            }
+        });
+    };
+
+    var bindNames = function(stmt, names) {
+        if ( Array.isArray(names) === false || names.length === 0 ) {
+            return;
+        }
+        var params = stmt.newBindingParamsArray();
+        var i = names.length, bp;
+        while ( i-- ) {
+            bp = params.newBindingParams();
+            bp.bindByName('name', names[i]);
+            params.addParams(bp);
+        }
+        stmt.bindParameters(params);
+    };
+
+    var clear = function(callback) {
+        if ( open() === null ) {
+            if ( typeof callback === 'function' ) {
+                callback();
+            }
+            return;
+        }
+        runStatement(db.createAsyncStatement('DELETE FROM "settings";'), callback);
+    };
+
+    var getBytesInUse = function(keys, callback) {
+        if ( typeof callback !== 'function' ) {
+            return;
+        }
+
+        if ( open() === null ) {
+            callback(0);
+            return;
+        }
+
+        var stmt;
+        if ( Array.isArray(keys) ) {
+            stmt = db.createAsyncStatement('SELECT "size" AS "size", SUM(LENGTH("value")) FROM "settings" WHERE "name" = :name');
+            bindNames(keys);
+        } else {
+            stmt = db.createAsyncStatement('SELECT "size" AS "size", SUM(LENGTH("value")) FROM "settings"');
+        }
+
+        runStatement(stmt, function(result) {
+            callback(result.size);
+        });
+    };
+
+    var read = function(details, callback) {
+        if ( typeof callback !== 'function' ) {
+            return;
+        }
+
+        var prepareResult = function(result) {
+            var key;
+            for ( key in result ) {
+                if ( result.hasOwnProperty(key) === false ) {
+                    continue;
+                }
+                result[key] = JSON.parse(result[key]);
+            }
+            if ( typeof details === 'object' && details !== null ) {
+                for ( key in details ) {
+                    if ( result.hasOwnProperty(key) === false ) {
+                        result[key] = details[key];
+                    }
+                }
+            }
+            callback(result);
+        };
+
+        if ( open() === null ) {
+            prepareResult({});
+            return;
+        }
+
+        var names = [];
+        if ( details !== null ) {
+            if ( Array.isArray(details) ) {
+                names = details;
+            } else if ( typeof details === 'object' ) {
+                names = Object.keys(details);
+            } else {
+                names = [details.toString()];
+            }
+        }
+
+        var stmt;
+        if ( names.length === 0 ) {
+            stmt = db.createAsyncStatement('SELECT * FROM "settings"');
+        } else {
+            stmt = db.createAsyncStatement('SELECT * FROM "settings" WHERE "name" = :name');
+            bindNames(stmt, names);
+        }
+
+        runStatement(stmt, prepareResult);
+    };
+
+    var remove = function(keys, callback) {
+        if ( open() === null ) {
+            if ( typeof callback === 'function' ) {
+                callback();
+            }
+            return;
+        }
+        var stmt = db.createAsyncStatement('DELETE FROM "settings" WHERE "name" = :name');
+        bindNames(stmt, typeof keys === 'string' ? [keys] : keys);
+        runStatement(stmt, callback);
+    };
+
+    var write = function(details, callback) {
+        if ( open() === null ) {
+            if ( typeof callback === 'function' ) {
+                callback();
+            }
+            return;
+        }
+
+        var stmt = db.createAsyncStatement('INSERT OR REPLACE INTO "settings" ("name", "value") VALUES(:name, :value)');
+        var params = stmt.newBindingParamsArray(), bp;
+        for ( var key in details ) {
+            if ( details.hasOwnProperty(key) === false ) {
+                continue;
+            }
+            bp = params.newBindingParams();
+            bp.bindByName('name', key);
+            bp.bindByName('value', JSON.stringify(details[key]));
+            params.addParams(bp);
+        }
+        if ( params.length === 0 ) {
+            return;
+        }
+
+        stmt.bindParameters(params);
+        runStatement(stmt, callback);
+    };
+
+    // Export API
+    var api = {
+        QUOTA_BYTES: 100 * 1024 * 1024,
+        clear: clear,
+        get: read,
+        getBytesInUse: getBytesInUse,
+        remove: remove,
+        set: write
+    };
+    return api;
+})();
+
+vAPI.cacheStorage = vAPI.storage;
+
+/******************************************************************************/
+
+// This must be executed/setup early.
+
+var winWatcher = (function() {
+    var windowToIdMap = new Map();
+    var windowIdGenerator = 1;
+    var api = {
+        onOpenWindow: null,
+        onCloseWindow: null
+    };
+
+    // https://github.com/gorhill/uMatrix/issues/586
+    // This is necessary hack because on SeaMonkey 2.40, for unknown reasons
+    // private windows do not have the attribute `windowtype` set to
+    // `navigator:browser`. As a fallback, the code here will also test whether
+    // the id attribute is `main-window`.
+    api.toBrowserWindow = function(win) {
+        var docElement = win && win.document && win.document.documentElement;
+        if ( !docElement ) {
+            return null;
+        }
+        if ( vAPI.thunderbird ) {
+            return docElement.getAttribute('windowtype') === 'mail:3pane' ? win : null;
+        }
+        return docElement.getAttribute('windowtype') === 'navigator:browser' ||
+               docElement.getAttribute('id') === 'main-window' ?
+               win : null;
+    };
+
+    api.getWindows = function() {
+        return windowToIdMap.keys();
+    };
+
+    api.idFromWindow = function(win) {
+        return windowToIdMap.get(win) || 0;
+    };
+
+    api.getCurrentWindow = function() {
+        return this.toBrowserWindow(Services.wm.getMostRecentWindow(null));
+    };
+
+    var addWindow = function(win) {
+        if ( !win || windowToIdMap.has(win) ) {
+            return;
+        }
+        windowToIdMap.set(win, windowIdGenerator++);
+        if ( typeof api.onOpenWindow === 'function' ) {
+            api.onOpenWindow(win);
+        }
+    };
+
+    var removeWindow = function(win) {
+        if ( !win || windowToIdMap.delete(win) !== true ) {
+            return;
+        }
+        if ( typeof api.onCloseWindow === 'function' ) {
+            api.onCloseWindow(win);
+        }
+    };
+
+    // https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XPCOM/Reference/Interface/nsIWindowMediator
+    // https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XPCOM/Reference/Interface/nsIWindowWatcher
+    // https://github.com/gorhill/uMatrix/issues/357
+    // Use nsIWindowMediator for being notified of opened/closed windows.
+    var listeners = {
+        onOpenWindow: function(aWindow) {
+            var win;
+            try {
+                win = aWindow.QueryInterface(Ci.nsIInterfaceRequestor)
+                             .getInterface(Ci.nsIDOMWindow);
+            } catch (ex) {
+            }
+            addWindow(win);
+        },
+
+        onCloseWindow: function(aWindow) {
+            var win;
+            try {
+                win = aWindow.QueryInterface(Ci.nsIInterfaceRequestor)
+                             .getInterface(Ci.nsIDOMWindow);
+            } catch (ex) {
+            }
+            removeWindow(win);
+        },
+
+        observe: function(aSubject, topic) {
+            // https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XPCOM/Reference/Interface/nsIWindowWatcher#registerNotification%28%29
+            //   "aSubject - the window being opened or closed, sent as an
+            //   "nsISupports which can be ... QueryInterfaced to an
+            //   "nsIDOMWindow."
+            var win;
+            try {
+                win = aSubject.QueryInterface(Ci.nsIInterfaceRequestor)
+                              .getInterface(Ci.nsIDOMWindow);
+            } catch (ex) {
+            }
+            if ( !win ) { return; }
+            if ( topic === 'domwindowopened' ) {
+                addWindow(win);
+                return;
+            }
+            if ( topic === 'domwindowclosed' ) {
+                removeWindow(win);
+                return;
+            }
+        }
+    };
+
+    (function() {
+        var winumerator, win;
+
+        // https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XPCOM/Reference/Interface/nsIWindowMediator#getEnumerator%28%29
+        winumerator = Services.wm.getEnumerator(null);
+        while ( winumerator.hasMoreElements() ) {
+            win = winumerator.getNext();
+            if ( !win.closed ) {
+                windowToIdMap.set(win, windowIdGenerator++);
+            }
+        }
+
+        // https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XPCOM/Reference/Interface/nsIWindowWatcher#getWindowEnumerator%28%29
+        winumerator = Services.ww.getWindowEnumerator();
+        while ( winumerator.hasMoreElements() ) {
+            win = winumerator.getNext()
+                             .QueryInterface(Ci.nsIInterfaceRequestor)
+                             .getInterface(Ci.nsIDOMWindow);
+            if ( !win.closed ) {
+                windowToIdMap.set(win, windowIdGenerator++);
+            }
+        }
+
+        Services.wm.addListener(listeners);
+        Services.ww.registerNotification(listeners);
+    })();
+
+    cleanupTasks.push(function() {
+        Services.wm.removeListener(listeners);
+        Services.ww.unregisterNotification(listeners);
+        windowToIdMap.clear();
+    });
+
+    return api;
+})();
+
+/******************************************************************************/
+
+var getTabBrowser = function(win) {
+    return win && win.gBrowser || null;
+};
+
+/******************************************************************************/
+
+var getOwnerWindow = function(target) {
+    if ( target.ownerDocument ) {
+        return target.ownerDocument.defaultView;
+    }
+    return null;
+};
+
+/******************************************************************************/
+
+vAPI.isBehindTheSceneTabId = function(tabId) {
+    return tabId.toString() === '-1';
+};
+
+vAPI.noTabId = '-1';
+
+/******************************************************************************/
+
+vAPI.tabs = {};
+
+/******************************************************************************/
+
+vAPI.tabs.registerListeners = function() {
+    tabWatcher.start();
+};
+
+/******************************************************************************/
+
+// Firefox:
+//   https://developer.mozilla.org/en-US/Add-ons/Code_snippets/Tabbed_browser
+//
+// browser --> ownerDocument --> defaultView --> gBrowser --> browsers --+
+//    ^                                                                  |
+//    |                                                                  |
+//    +-------------------------------------------------------------------
+//
+// browser (browser)
+//   contentTitle
+//   currentURI
+//   ownerDocument (XULDocument)
+//     defaultView (ChromeWindow)
+//     gBrowser (tabbrowser OR browser)
+//       browsers (browser)
+//       selectedBrowser
+//       selectedTab
+//       tabs (tab.tabbrowser-tab)
+//
+// Fennec: (what I figured so far)
+//
+//   tab --> browser     windows --> window --> BrowserApp --> tabs --+
+//    ^      window                                                   |
+//    |                                                               |
+//    +---------------------------------------------------------------+
+//
+// tab
+//   browser
+// [manual search to go back to tab from list of windows]
+
+vAPI.tabs.get = function(tabId, callback) {
+    var browser;
+
+    if ( tabId === null ) {
+        browser = tabWatcher.currentBrowser();
+        tabId = tabWatcher.tabIdFromTarget(browser);
+    } else {
+        browser = tabWatcher.browserFromTabId(tabId);
+    }
+
+    // For internal use
+    if ( typeof callback !== 'function' ) {
+        return browser;
+    }
+
+    if ( !browser || !browser.currentURI ) {
+        callback();
+        return;
+    }
+
+    var win = getOwnerWindow(browser);
+    var tabBrowser = getTabBrowser(win);
+
+    // https://github.com/gorhill/uMatrix/issues/540
+    // The `index` property is nowhere used by uMatrix at this point, so we
+    // will refrain from returning this information for the time being.
+
+    callback({
+        id: tabId,
+        index: undefined,
+        windowId: winWatcher.idFromWindow(win),
+        active: tabBrowser !== null && browser === tabBrowser.selectedBrowser,
+        url: browser.currentURI.asciiSpec,
+        title: browser.contentTitle
+    });
+};
+
+/******************************************************************************/
+
+vAPI.tabs.getAllSync = function(window) {
+    var win, tab;
+    var tabs = [];
+
+    for ( win of winWatcher.getWindows() ) {
+        if ( window && window !== win ) {
+            continue;
+        }
+
+        var tabBrowser = getTabBrowser(win);
+        if ( tabBrowser === null ) {
+            continue;
+        }
+
+        // This can happens if a tab-less window is currently opened.
+        // Example of a tab-less window: one opened from clicking
+        //   "View Page Source".
+        if ( !tabBrowser.tabs ) {
+            continue;
+        }
+
+        for ( tab of tabBrowser.tabs ) {
+            tabs.push(tab);
+        }
+    }
+
+    return tabs;
+};
+
+/******************************************************************************/
+
+vAPI.tabs.getAll = function(callback) {
+    var tabs = [], tab;
+
+    for ( var browser of tabWatcher.browsers() ) {
+        tab = tabWatcher.tabFromBrowser(browser);
+        if ( tab === null ) {
+            continue;
+        }
+        if ( tab.hasAttribute('pending') ) {
+            continue;
+        }
+        tabs.push({
+            id: tabWatcher.tabIdFromTarget(browser),
+            url: browser.currentURI.asciiSpec
+        });
+    }
+
+    callback(tabs);
+};
+
+/******************************************************************************/
+
+// properties of the details object:
+//   url: 'URL', // the address that will be opened
+//   tabId: 1, // the tab is used if set, instead of creating a new one
+//   index: -1, // undefined: end of the list, -1: following tab, or after index
+//   active: false, // opens the tab in background - true and undefined: foreground
+//   select: true // if a tab is already opened with that url, then select it instead of opening a new one
+
+vAPI.tabs.open = function(details) {
+    if ( !details.url ) {
+        return null;
+    }
+    // extension pages
+    if ( /^[\w-]{2,}:/.test(details.url) === false ) {
+        details.url = vAPI.getURL(details.url);
+    }
+
+    var tab;
+
+    if ( details.select ) {
+        var URI = Services.io.newURI(details.url, null, null);
+
+        for ( tab of this.getAllSync() ) {
+            var browser = tabWatcher.browserFromTarget(tab);
+            // https://github.com/gorhill/uBlock/issues/2558
+            if ( browser === null ) { continue; }
+
+            // Or simply .equals if we care about the fragment
+            if ( URI.equalsExceptRef(browser.currentURI) === false ) {
+                continue;
+            }
+
+            this.select(tab);
+
+            // Update URL if fragment is different
+            if ( URI.equals(browser.currentURI) === false ) {
+                browser.loadURI(URI.asciiSpec);
+            }
+            return;
+        }
+    }
+
+    if ( details.active === undefined ) {
+        details.active = true;
+    }
+
+    if ( details.tabId ) {
+        tab = tabWatcher.browserFromTabId(details.tabId);
+        if ( tab ) {
+            tabWatcher.browserFromTarget(tab).loadURI(details.url);
+            return;
+        }
+    }
+
+    // Open in a standalone window
+    if ( details.popup === true ) {
+        Services.ww.openWindow(
+            self,
+            details.url,
+            null,
+            'location=1,menubar=1,personalbar=1,resizable=1,toolbar=1',
+            null
+        );
+        return;
+    }
+
+    var win = winWatcher.getCurrentWindow();
+    var tabBrowser = getTabBrowser(win);
+    if ( tabBrowser === null ) {
+        return;
+    }
+
+    if ( details.index === -1 ) {
+        details.index = tabBrowser.browsers.indexOf(tabBrowser.selectedBrowser) + 1;
+    }
+
+    tab = tabBrowser.loadOneTab(details.url, { inBackground: !details.active });
+
+    if ( details.index !== undefined ) {
+        tabBrowser.moveTabTo(tab, details.index);
+    }
+};
+
+/******************************************************************************/
+
+// Replace the URL of a tab. Noop if the tab does not exist.
+
+vAPI.tabs.replace = function(tabId, url) {
+    var targetURL = url;
+
+    // extension pages
+    if ( /^[\w-]{2,}:/.test(targetURL) !== true ) {
+        targetURL = vAPI.getURL(targetURL);
+    }
+
+    var browser = tabWatcher.browserFromTabId(tabId);
+    if ( browser ) {
+        browser.loadURI(targetURL);
+    }
+};
+
+/******************************************************************************/
+
+vAPI.tabs._remove = function(tab, tabBrowser) {
+    if ( tabBrowser ) {
+        tabBrowser.removeTab(tab);
+    }
+};
+
+/******************************************************************************/
+
+vAPI.tabs.remove = function(tabId) {
+    var browser = tabWatcher.browserFromTabId(tabId);
+    if ( !browser ) {
+        return;
+    }
+    var tab = tabWatcher.tabFromBrowser(browser);
+    if ( !tab ) {
+        return;
+    }
+    this._remove(tab, getTabBrowser(getOwnerWindow(browser)));
+};
+
+/******************************************************************************/
+
+vAPI.tabs.reload = function(tabId) {
+    var browser = tabWatcher.browserFromTabId(tabId);
+    if ( !browser ) {
+        return;
+    }
+
+    browser.webNavigation.reload(Ci.nsIWebNavigation.LOAD_FLAGS_BYPASS_CACHE);
+};
+
+/******************************************************************************/
+
+vAPI.tabs.select = function(tab) {
+    if ( typeof tab !== 'object' ) {
+        tab = tabWatcher.tabFromBrowser(tabWatcher.browserFromTabId(tab));
+    }
+    if ( !tab ) {
+        return;
+    }
+
+    // https://github.com/gorhill/uBlock/issues/470
+    var win = getOwnerWindow(tab);
+    win.focus();
+
+    var tabBrowser = getTabBrowser(win);
+    if ( tabBrowser ) {
+        tabBrowser.selectedTab = tab;
+    }
+};
+
+/******************************************************************************/
+
+vAPI.tabs.injectScript = function(tabId, details, callback) {
+    var browser = tabWatcher.browserFromTabId(tabId);
+    if ( !browser ) {
+        return;
+    }
+
+    if ( typeof details.file !== 'string' ) {
+        return;
+    }
+
+    details.file = vAPI.getURL(details.file);
+    browser.messageManager.sendAsyncMessage(
+        location.host + ':broadcast',
+        JSON.stringify({
+            broadcast: true,
+            channelName: 'vAPI',
+            msg: {
+                cmd: 'injectScript',
+                details: details
+            }
+        })
+    );
+
+    if ( typeof callback === 'function' ) {
+        vAPI.setTimeout(callback, 13);
+    }
+};
+
+/******************************************************************************/
+
+var tabWatcher = (function() {
+    // TODO: find out whether we need a janitor to take care of stale entries.
+
+    // https://github.com/gorhill/uMatrix/issues/540
+    // Use only weak references to hold onto browser references.
+    var browserToTabIdMap = new WeakMap();
+    var tabIdToBrowserMap = new Map();
+    var tabIdGenerator = 1;
+
+    var indexFromBrowser = function(browser) {
+        if ( !browser ) {
+            return -1;
+        }
+        var win = getOwnerWindow(browser);
+        if ( !win ) {
+            return -1;
+        }
+        var tabBrowser = getTabBrowser(win);
+        if ( tabBrowser === null ) {
+            return -1;
+        }
+        // This can happen, for example, the `view-source:` window, there is
+        // no tabbrowser object, the browser object sits directly in the
+        // window.
+        if ( tabBrowser === browser ) {
+            return 0;
+        }
+        return tabBrowser.browsers.indexOf(browser);
+    };
+
+    var indexFromTarget = function(target) {
+        return indexFromBrowser(browserFromTarget(target));
+    };
+
+    var tabFromBrowser = function(browser) {
+        var i = indexFromBrowser(browser);
+        if ( i === -1 ) {
+            return null;
+        }
+        var win = getOwnerWindow(browser);
+        if ( !win ) {
+            return null;
+        }
+        var tabBrowser = getTabBrowser(win);
+        if ( tabBrowser === null ) {
+            return null;
+        }
+        if ( !tabBrowser.tabs || i >= tabBrowser.tabs.length ) {
+            return null;
+        }
+        return tabBrowser.tabs[i];
+    };
+
+    var browserFromTarget = function(target) {
+        if ( !target ) {
+            return null;
+        }
+        if ( target.linkedPanel ) {  // target is a tab
+            target = target.linkedBrowser;
+        }
+        if ( target.localName !== 'browser' ) {
+            return null;
+        }
+        return target;
+    };
+
+    var tabIdFromTarget = function(target) {
+        var browser = browserFromTarget(target);
+        if ( browser === null ) {
+            return vAPI.noTabId;
+        }
+        var tabId = browserToTabIdMap.get(browser);
+        if ( tabId === undefined ) {
+            tabId = '' + tabIdGenerator++;
+            browserToTabIdMap.set(browser, tabId);
+            tabIdToBrowserMap.set(tabId, Cu.getWeakReference(browser));
+        }
+        return tabId;
+    };
+
+    var browserFromTabId = function(tabId) {
+        var weakref = tabIdToBrowserMap.get(tabId);
+        var browser = weakref && weakref.get();
+        return browser || null;
+    };
+
+    var currentBrowser = function() {
+        var win = winWatcher.getCurrentWindow();
+        // https://github.com/gorhill/uBlock/issues/399
+        // getTabBrowser() can return null at browser launch time.
+        var tabBrowser = getTabBrowser(win);
+        if ( tabBrowser === null ) {
+            return null;
+        }
+        return browserFromTarget(tabBrowser.selectedTab);
+    };
+
+    var removeBrowserEntry = function(tabId, browser) {
+        if ( tabId && tabId !== vAPI.noTabId ) {
+            vAPI.tabs.onClosed(tabId);
+            delete vAPI.toolbarButton.tabs[tabId];
+            tabIdToBrowserMap.delete(tabId);
+        }
+        if ( browser ) {
+            browserToTabIdMap.delete(browser);
+        }
+    };
+
+    var removeTarget = function(target) {
+        onClose({ target: target });
+    };
+
+    var getAllBrowsers = function() {
+        var browsers = [], browser;
+        for ( var [tabId, weakref] of tabIdToBrowserMap ) {
+            browser = weakref.get();
+            // TODO:
+            // Maybe call removeBrowserEntry() if the browser no longer exists?
+            if ( browser ) {
+                browsers.push(browser);
+            }
+        }
+        return browsers;
+    };
+
+    // https://developer.mozilla.org/en-US/docs/Web/Events/TabOpen
+    //var onOpen = function({target}) {
+    //    var tabId = tabIdFromTarget(target);
+    //    var browser = browserFromTabId(tabId);
+    //    vAPI.tabs.onNavigation({
+    //        frameId: 0,
+    //        tabId: tabId,
+    //        url: browser.currentURI.asciiSpec,
+    //    });
+    //};
+
+    // https://developer.mozilla.org/en-US/docs/Web/Events/TabShow
+    var onShow = function({target}) {
+        tabIdFromTarget(target);
+    };
+
+    // https://developer.mozilla.org/en-US/docs/Web/Events/TabClose
+    var onClose = function({target}) {
+        // target is tab in Firefox, browser in Fennec
+        var browser = browserFromTarget(target);
+        var tabId = browserToTabIdMap.get(browser);
+        removeBrowserEntry(tabId, browser);
+    };
+
+    // https://developer.mozilla.org/en-US/docs/Web/Events/TabSelect
+    // This is an entry point: when creating a new tab, it is not always
+    // reported through onLocationChanged... Sigh. It is "reported" here
+    // however.
+    var onSelect = function({target}) {
+        var browser = browserFromTarget(target);
+        var tabId = browserToTabIdMap.get(browser);
+        if ( tabId === undefined ) {
+            tabId = tabIdFromTarget(target);
+            vAPI.tabs.onNavigation({
+                frameId: 0,
+                tabId: tabId,
+                url: browser.currentURI.asciiSpec
+            });
+        }
+        vAPI.setIcon(tabId, getOwnerWindow(target));
+    };
+
+    var locationChangedMessageName = location.host + ':locationChanged';
+
+    var onLocationChanged = function(e) {
+        var vapi = vAPI;
+        var details = e.data;
+
+        // Ignore notifications related to our popup
+        if ( details.url.lastIndexOf(vapi.getURL('popup.html'), 0) === 0 ) {
+            return;
+        }
+
+        var browser = e.target;
+        var tabId = tabIdFromTarget(browser);
+        if ( tabId === vapi.noTabId ) {
+            return;
+        }
+
+        // LOCATION_CHANGE_SAME_DOCUMENT = "did not load a new document"
+        if ( details.flags & Ci.nsIWebProgressListener.LOCATION_CHANGE_SAME_DOCUMENT ) {
+            vapi.tabs.onUpdated(tabId, {url: details.url}, {
+                frameId: 0,
+                tabId: tabId,
+                url: browser.currentURI.asciiSpec
+            });
+            return;
+        }
+
+        // https://github.com/chrisaljoudi/uBlock/issues/105
+        // Allow any kind of pages
+        vapi.tabs.onNavigation({
+            frameId: 0,
+            tabId: tabId,
+            url: details.url
+        });
+    };
+
+    var attachToTabBrowser = function(window) {
+        if ( typeof vAPI.toolbarButton.attachToNewWindow === 'function' ) {
+            vAPI.toolbarButton.attachToNewWindow(window);
+        }
+
+        var tabBrowser = getTabBrowser(window);
+        if ( tabBrowser === null ) {
+            return;
+        }
+
+        var tabContainer;
+        if ( tabBrowser.deck ) {                    // Fennec
+            tabContainer = tabBrowser.deck;
+        } else if ( tabBrowser.tabContainer ) {     // Firefox
+            tabContainer = tabBrowser.tabContainer;
+            vAPI.contextMenu.register(document);
+        }
+
+        // https://github.com/gorhill/uBlock/issues/697
+        // Ignore `TabShow` events: unfortunately the `pending` attribute is
+        // not set when a tab is opened as a result of session restore -- it is
+        // set *after* the event is fired in such case.
+        if ( tabContainer ) {
+            tabContainer.addEventListener('TabShow', onShow);
+            tabContainer.addEventListener('TabClose', onClose);
+            // when new window is opened TabSelect doesn't run on the selected tab?
+            tabContainer.addEventListener('TabSelect', onSelect);
+        }
+    };
+
+    // https://github.com/gorhill/uBlock/issues/906
+    // Ensure the environment is ready before trying to attaching.
+    var canAttachToTabBrowser = function(window) {
+        var document = window && window.document;
+        if ( !document || document.readyState !== 'complete' ) {
+            return false;
+        }
+
+        // On some platforms, the tab browser isn't immediately available,
+        // try waiting a bit if this happens.
+        // https://github.com/gorhill/uBlock/issues/763
+        // Not getting a tab browser should not prevent from attaching ourself
+        // to the window.
+        var tabBrowser = getTabBrowser(window);
+        if ( tabBrowser === null ) {
+            return false;
+        }
+
+        return winWatcher.toBrowserWindow(window) !== null;
+    };
+
+    var onWindowLoad = function(win) {
+        deferUntil(
+            canAttachToTabBrowser.bind(null, win),
+            attachToTabBrowser.bind(null, win)
+        );
+    };
+
+    var onWindowUnload = function(win) {
+        vAPI.contextMenu.unregister(win.document);
+
+        var tabBrowser = getTabBrowser(win);
+        if ( tabBrowser === null ) {
+            return;
+        }
+
+        var tabContainer = tabBrowser.tabContainer;
+        if ( tabContainer ) {
+            tabContainer.removeEventListener('TabShow', onShow);
+            tabContainer.removeEventListener('TabClose', onClose);
+            tabContainer.removeEventListener('TabSelect', onSelect);
+        }
+
+        // https://github.com/gorhill/uBlock/issues/574
+        // To keep in mind: not all windows are tab containers,
+        // sometimes the window IS the tab.
+        var tabs;
+        if ( tabBrowser.tabs ) {
+            tabs = tabBrowser.tabs;
+        } else if ( tabBrowser.localName === 'browser' ) {
+            tabs = [tabBrowser];
+        } else {
+            tabs = [];
+        }
+
+        var browser, URI, tabId;
+        var tabindex = tabs.length, tab;
+        while ( tabindex-- ) {
+            tab = tabs[tabindex];
+            browser = browserFromTarget(tab);
+            if ( browser === null ) {
+                continue;
+            }
+            URI = browser.currentURI;
+            // Close extension tabs
+            if ( URI.schemeIs('chrome') && URI.host === location.host ) {
+                vAPI.tabs._remove(tab, getTabBrowser(win));
+            }
+            tabId = browserToTabIdMap.get(browser);
+            if ( tabId !== undefined ) {
+                removeBrowserEntry(tabId, browser);
+                tabIdToBrowserMap.delete(tabId);
+            }
+            browserToTabIdMap.delete(browser);
+        }
+    };
+
+    // Initialize map with existing active tabs
+    var start = function() {
+        var tabBrowser, tabs, tab;
+        for ( var win of winWatcher.getWindows() ) {
+            onWindowLoad(win);
+            tabBrowser = getTabBrowser(win);
+            if ( tabBrowser === null ) {
+                continue;
+            }
+            for ( tab of tabBrowser.tabs ) {
+                if ( !tab.hasAttribute('pending') ) {
+                    tabIdFromTarget(tab);
+                }
+            }
+        }
+
+        winWatcher.onOpenWindow = onWindowLoad;
+        winWatcher.onCloseWindow = onWindowUnload;
+
+        vAPI.messaging.globalMessageManager.addMessageListener(
+            locationChangedMessageName,
+            onLocationChanged
+        );
+    };
+
+    var stop = function() {
+        winWatcher.onOpenWindow = null;
+        winWatcher.onCloseWindow = null;
+
+        vAPI.messaging.globalMessageManager.removeMessageListener(
+            locationChangedMessageName,
+            onLocationChanged
+        );
+
+        for ( var win of winWatcher.getWindows() ) {
+            onWindowUnload(win);
+        }
+
+        browserToTabIdMap = new WeakMap();
+        tabIdToBrowserMap.clear();
+    };
+
+    cleanupTasks.push(stop);
+
+    return {
+        browsers: getAllBrowsers,
+        browserFromTabId: browserFromTabId,
+        browserFromTarget: browserFromTarget,
+        currentBrowser: currentBrowser,
+        indexFromTarget: indexFromTarget,
+        removeTarget: removeTarget,
+        start: start,
+        tabFromBrowser: tabFromBrowser,
+        tabIdFromTarget: tabIdFromTarget
+    };
+})();
+
+/******************************************************************************/
+
+vAPI.setIcon = function(tabId, iconId, badge) {
+    // If badge is undefined, then setIcon was called from the TabSelect event
+    var win;
+    if ( badge === undefined ) {
+        win = iconId;
+    } else {
+        win = winWatcher.getCurrentWindow();
+    }
+    var tabBrowser = getTabBrowser(win);
+    if ( tabBrowser === null ) {
+        return;
+    }
+    var curTabId = tabWatcher.tabIdFromTarget(tabBrowser.selectedTab);
+    var tb = vAPI.toolbarButton;
+
+    // from 'TabSelect' event
+    if ( tabId === undefined ) {
+        tabId = curTabId;
+    } else if ( badge !== undefined ) {
+        tb.tabs[tabId] = { badge: badge, img: iconId };
+    }
+
+    if ( tabId === curTabId ) {
+        tb.updateState(win, tabId);
+    }
+};
+
+/******************************************************************************/
+
+vAPI.messaging = {
+    get globalMessageManager() {
+        return Cc['@mozilla.org/globalmessagemanager;1']
+                .getService(Ci.nsIMessageListenerManager);
+    },
+    frameScript: vAPI.getURL('frameScript.js'),
+    listeners: {},
+    defaultHandler: null,
+    NOOPFUNC: function(){},
+    UNHANDLED: 'vAPI.messaging.notHandled'
+};
+
+/******************************************************************************/
+
+vAPI.messaging.listen = function(listenerName, callback) {
+    this.listeners[listenerName] = callback;
+};
+
+/******************************************************************************/
+
+vAPI.messaging.onMessage = function({target, data}) {
+    var messageManager = target.messageManager;
+
+    if ( !messageManager ) {
+        // Message came from a popup, and its message manager is not usable.
+        // So instead we broadcast to the parent window.
+        messageManager = getOwnerWindow(
+            target.webNavigation.QueryInterface(Ci.nsIDocShell).chromeEventHandler
+        ).messageManager;
+    }
+
+    var channelNameRaw = data.channelName;
+    var pos = channelNameRaw.indexOf('|');
+    var channelName = channelNameRaw.slice(pos + 1);
+
+    var callback = vAPI.messaging.NOOPFUNC;
+    if ( data.requestId !== undefined ) {
+        callback = CallbackWrapper.factory(
+            messageManager,
+            channelName,
+            channelNameRaw.slice(0, pos),
+            data.requestId
+        ).callback;
+    }
+
+    var sender = {
+        tab: {
+            id: tabWatcher.tabIdFromTarget(target)
+        }
+    };
+
+    // Specific handler
+    var r = vAPI.messaging.UNHANDLED;
+    var listener = vAPI.messaging.listeners[channelName];
+    if ( typeof listener === 'function' ) {
+        r = listener(data.msg, sender, callback);
+    }
+    if ( r !== vAPI.messaging.UNHANDLED ) {
+        return;
+    }
+
+    // Default handler
+    r = vAPI.messaging.defaultHandler(data.msg, sender, callback);
+    if ( r !== vAPI.messaging.UNHANDLED ) {
+        return;
+    }
+
+    console.error('uMatrix> messaging > unknown request: %o', data);
+
+    // Unhandled:
+    // Need to callback anyways in case caller expected an answer, or
+    // else there is a memory leak on caller's side
+    callback();
+};
+
+/******************************************************************************/
+
+vAPI.messaging.setup = function(defaultHandler) {
+    // Already setup?
+    if ( this.defaultHandler !== null ) {
+        return;
+    }
+
+    if ( typeof defaultHandler !== 'function' ) {
+        defaultHandler = function(){ return vAPI.messaging.UNHANDLED; };
+    }
+    this.defaultHandler = defaultHandler;
+
+    this.globalMessageManager.addMessageListener(
+        location.host + ':background',
+        this.onMessage
+    );
+
+    this.globalMessageManager.loadFrameScript(this.frameScript, true);
+
+    cleanupTasks.push(function() {
+        var gmm = vAPI.messaging.globalMessageManager;
+
+        gmm.removeDelayedFrameScript(vAPI.messaging.frameScript);
+        gmm.removeMessageListener(
+            location.host + ':background',
+            vAPI.messaging.onMessage
+        );
+    });
+};
+
+/******************************************************************************/
+
+vAPI.messaging.broadcast = function(message) {
+    this.globalMessageManager.broadcastAsyncMessage(
+        location.host + ':broadcast',
+        JSON.stringify({broadcast: true, msg: message})
+    );
+};
+
+/******************************************************************************/
+
+// This allows to avoid creating a closure for every single message which
+// expects an answer. Having a closure created each time a message is processed
+// has been always bothering me. Another benefit of the implementation here
+// is to reuse the callback proxy object, so less memory churning.
+//
+// https://developers.google.com/speed/articles/optimizing-javascript
+// "Creating a closure is significantly slower then creating an inner
+//  function without a closure, and much slower than reusing a static
+//  function"
+//
+// http://hacksoflife.blogspot.ca/2015/01/the-four-horsemen-of-performance.html
+// "the dreaded 'uniformly slow code' case where every function takes 1%
+//  of CPU and you have to make one hundred separate performance optimizations
+//  to improve performance at all"
+//
+// http://jsperf.com/closure-no-closure/2
+
+var CallbackWrapper = function(messageManager, channelName, listenerId, requestId) {
+    this.callback = this.proxy.bind(this); // bind once
+    this.init(messageManager, channelName, listenerId, requestId);
+};
+
+CallbackWrapper.junkyard = [];
+
+CallbackWrapper.factory = function(messageManager, channelName, listenerId, requestId) {
+    var wrapper = CallbackWrapper.junkyard.pop();
+    if ( wrapper ) {
+        wrapper.init(messageManager, channelName, listenerId, requestId);
+        return wrapper;
+    }
+    return new CallbackWrapper(messageManager, channelName, listenerId, requestId);
+};
+
+CallbackWrapper.prototype.init = function(messageManager, channelName, listenerId, requestId) {
+    this.messageManager = messageManager;
+    this.channelName = channelName;
+    this.listenerId = listenerId;
+    this.requestId = requestId;
+};
+
+CallbackWrapper.prototype.proxy = function(response) {
+    var message = JSON.stringify({
+        requestId: this.requestId,
+        channelName: this.channelName,
+        msg: response !== undefined ? response : null
+    });
+
+    if ( this.messageManager.sendAsyncMessage ) {
+        this.messageManager.sendAsyncMessage(this.listenerId, message);
+    } else {
+        this.messageManager.broadcastAsyncMessage(this.listenerId, message);
+    }
+
+    // Mark for reuse
+    this.messageManager =
+    this.channelName =
+    this.requestId =
+    this.listenerId = null;
+    CallbackWrapper.junkyard.push(this);
+};
+
+/******************************************************************************/
+
+var httpRequestHeadersFactory = function(channel) {
+    var entry = httpRequestHeadersFactory.junkyard.pop();
+    if ( entry ) {
+        return entry.init(channel);
+    }
+    return new HTTPRequestHeaders(channel);
+};
+
+httpRequestHeadersFactory.junkyard = [];
+
+var HTTPRequestHeaders = function(channel) {
+    this.init(channel);
+};
+
+HTTPRequestHeaders.prototype.init = function(channel) {
+    this.channel = channel;
+    return this;
+};
+
+HTTPRequestHeaders.prototype.dispose = function() {
+    this.channel = null;
+    httpRequestHeadersFactory.junkyard.push(this);
+};
+
+HTTPRequestHeaders.prototype.getHeader = function(name) {
+    try {
+        return this.channel.getRequestHeader(name);
+    } catch (e) {
+    }
+    return '';
+};
+
+HTTPRequestHeaders.prototype.setHeader = function(name, newValue, create) {
+    var oldValue = this.getHeader(name);
+    if ( newValue === oldValue ) {
+        return false;
+    }
+    if ( oldValue === '' && create !== true ) {
+        return false;
+    }
+    this.channel.setRequestHeader(name, newValue, false);
+    return true;
+};
+
+/******************************************************************************/
+
+var httpObserver = {
+    classDescription: 'net-channel-event-sinks for ' + location.host,
+    classID: Components.ID('{5d2e2797-6d68-42e2-8aeb-81ce6ba16b95}'),
+    contractID: '@' + location.host + '/net-channel-event-sinks;1',
+    REQDATAKEY: location.host + 'reqdata',
+    ABORT: Components.results.NS_BINDING_ABORTED,
+    ACCEPT: Components.results.NS_SUCCEEDED,
+    // Request types:
+    // https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XPCOM/Reference/Interface/nsIContentPolicy#Constants
+    frameTypeMap: {
+        6: 'main_frame',
+        7: 'sub_frame'
+    },
+    typeMap: {
+        1: 'other',
+        2: 'script',
+        3: 'image',
+        4: 'stylesheet',
+        5: 'object',
+        6: 'main_frame',
+        7: 'sub_frame',
+        9: 'xbl',
+        10: 'ping',
+        11: 'xmlhttprequest',
+        12: 'object',
+        13: 'xml_dtd',
+        14: 'font',
+        15: 'media',
+        16: 'websocket',
+        17: 'csp_report',
+        18: 'xslt',
+        19: 'beacon',
+        20: 'xmlhttprequest',
+        21: 'imageset',
+        22: 'web_manifest'
+    },
+    mimeTypeMap: {
+        'audio': 15,
+        'video': 15
+    },
+
+    get componentRegistrar() {
+        return Components.manager.QueryInterface(Ci.nsIComponentRegistrar);
+    },
+
+    get categoryManager() {
+        return Cc['@mozilla.org/categorymanager;1']
+                .getService(Ci.nsICategoryManager);
+    },
+
+    QueryInterface: (function() {
+        var {XPCOMUtils} = Cu.import('resource://gre/modules/XPCOMUtils.jsm', null);
+
+        return XPCOMUtils.generateQI([
+            Ci.nsIFactory,
+            Ci.nsIObserver,
+            Ci.nsIChannelEventSink,
+            Ci.nsISupportsWeakReference
+        ]);
+    })(),
+
+    createInstance: function(outer, iid) {
+        if ( outer ) {
+            throw Components.results.NS_ERROR_NO_AGGREGATION;
+        }
+
+        return this.QueryInterface(iid);
+    },
+
+    register: function() {
+        this.pendingRingBufferInit();
+
+        // https://developer.mozilla.org/en/docs/Observer_Notifications#HTTP_requests
+        Services.obs.addObserver(this, 'http-on-modify-request', true);
+        Services.obs.addObserver(this, 'http-on-examine-response', true);
+        Services.obs.addObserver(this, 'http-on-examine-cached-response', true);
+
+        // Guard against stale instances not having been unregistered
+        if ( this.componentRegistrar.isCIDRegistered(this.classID) ) {
+            try {
+                this.componentRegistrar.unregisterFactory(this.classID, Components.manager.getClassObject(this.classID, Ci.nsIFactory));
+            } catch (ex) {
+                console.error('uMatrix> httpObserver > unable to unregister stale instance: ', ex);
+            }
+        }
+
+        this.componentRegistrar.registerFactory(
+            this.classID,
+            this.classDescription,
+            this.contractID,
+            this
+        );
+        this.categoryManager.addCategoryEntry(
+            'net-channel-event-sinks',
+            this.contractID,
+            this.contractID,
+            false,
+            true
+        );
+    },
+
+    unregister: function() {
+        Services.obs.removeObserver(this, 'http-on-modify-request');
+        Services.obs.removeObserver(this, 'http-on-examine-response');
+        Services.obs.removeObserver(this, 'http-on-examine-cached-response');
+
+        this.componentRegistrar.unregisterFactory(this.classID, this);
+        this.categoryManager.deleteCategoryEntry(
+            'net-channel-event-sinks',
+            this.contractID,
+            false
+        );
+    },
+
+    PendingRequest: function() {
+        this.rawType = 0;
+        this.tabId = 0;
+        this._key = ''; // key is url, from URI.spec
+    },
+
+    // If all work fine, this map should not grow indefinitely. It can have
+    // stale items in it, but these will be taken care of when entries in
+    // the ring buffer are overwritten.
+    pendingURLToIndex: new Map(),
+    pendingWritePointer: 0,
+    pendingRingBuffer: new Array(256),
+    pendingRingBufferInit: function() {
+        // Use and reuse pre-allocated PendingRequest objects = less memory
+        // churning.
+        var i = this.pendingRingBuffer.length;
+        while ( i-- ) {
+            this.pendingRingBuffer[i] = new this.PendingRequest();
+        }
+    },
+
+    // Pending request ring buffer:
+    // +-------+-------+-------+-------+-------+-------+-------
+    // |0      |1      |2      |3      |4      |5      |...      
+    // +-------+-------+-------+-------+-------+-------+-------
+    //
+    // URL to ring buffer index map:
+    // { k = URL, s = ring buffer indices }
+    //
+    // s is a string which character codes map to ring buffer indices -- for
+    // when the same URL is received multiple times by shouldLoadListener()
+    // before the existing one is serviced by the network request observer.
+    // I believe the use of a string in lieu of an array reduces memory
+    // churning.
+
+    createPendingRequest: function(url) {
+        var bucket;
+        var i = this.pendingWritePointer;
+        this.pendingWritePointer = i + 1 & 255;
+        var preq = this.pendingRingBuffer[i];
+        var si = String.fromCharCode(i);
+        // Cleanup unserviced pending request
+        if ( preq._key !== '' ) {
+            bucket = this.pendingURLToIndex.get(preq._key);
+            if ( bucket.length === 1 ) {
+                this.pendingURLToIndex.delete(preq._key);
+            } else {
+                var pos = bucket.indexOf(si);
+                this.pendingURLToIndex.set(preq._key, bucket.slice(0, pos) + bucket.slice(pos + 1));
+            }
+        }
+        bucket = this.pendingURLToIndex.get(url);
+        this.pendingURLToIndex.set(url, bucket === undefined ? si : bucket + si);
+        preq._key = url;
+        return preq;
+    },
+
+    lookupPendingRequest: function(url) {
+        var bucket = this.pendingURLToIndex.get(url);
+        if ( bucket === undefined ) {
+            return null;
+        }
+        var i = bucket.charCodeAt(0);
+        if ( bucket.length === 1 ) {
+            this.pendingURLToIndex.delete(url);
+        } else {
+            this.pendingURLToIndex.set(url, bucket.slice(1));
+        }
+        var preq = this.pendingRingBuffer[i];
+        preq._key = ''; // mark as "serviced"
+        return preq;
+    },
+
+    handleRequest: function(channel, URI, tabId, rawType) {
+        var type = this.typeMap[rawType] || 'other';
+
+        var onBeforeRequest = vAPI.net.onBeforeRequest;
+        if ( onBeforeRequest.types === null || onBeforeRequest.types.has(type) ) {
+            var result = onBeforeRequest.callback({
+                parentFrameId: type === 'main_frame' ? -1 : 0,
+                tabId: tabId,
+                type: type,
+                url: URI.asciiSpec
+            });
+            if ( typeof result === 'object' ) {
+                channel.cancel(this.ABORT);
+                return true;
+            }
+        }
+
+        var onBeforeSendHeaders = vAPI.net.onBeforeSendHeaders;
+        if ( onBeforeSendHeaders.types === null || onBeforeSendHeaders.types.has(type) ) {
+            var requestHeaders = httpRequestHeadersFactory(channel);
+            onBeforeSendHeaders.callback({
+                parentFrameId: type === 'main_frame' ? -1 : 0,
+                requestHeaders: requestHeaders,
+                tabId: tabId,
+                type: type,
+                url: URI.asciiSpec
+            });
+            requestHeaders.dispose();
+        }
+
+        return false;
+    },
+
+    channelDataFromChannel: function(channel) {
+        if ( channel instanceof Ci.nsIWritablePropertyBag ) {
+            try {
+                return channel.getProperty(this.REQDATAKEY) || null;
+            } catch (ex) {
+            }
+        }
+        return null;
+    },
+
+    // https://github.com/gorhill/uMatrix/issues/165
+    // https://developer.mozilla.org/en-US/Firefox/Releases/3.5/Updating_extensions#Getting_a_load_context_from_a_request
+    // Not sure `umatrix:shouldLoad` is still needed, uMatrix does not
+    //   care about embedded frames topography.
+    // Also:
+    //   https://developer.mozilla.org/en-US/Firefox/Multiprocess_Firefox/Limitations_of_chrome_scripts
+    tabIdFromChannel: function(channel) {
+        var lc;
+        try {
+            lc = channel.notificationCallbacks.getInterface(Ci.nsILoadContext);
+        } catch(ex) {
+        }
+        if ( !lc ) {
+            try {
+                lc = channel.loadGroup.notificationCallbacks.getInterface(Ci.nsILoadContext);
+            } catch(ex) {
+            }
+            if ( !lc ) {
+                return vAPI.noTabId;
+            }
+        }
+        if ( lc.topFrameElement ) {
+            return tabWatcher.tabIdFromTarget(lc.topFrameElement);
+        }
+        var win;
+        try {
+            win = lc.associatedWindow;
+        } catch (ex) { }
+        if ( !win ) {
+            return vAPI.noTabId;
+        }
+        if ( win.top ) {
+            win = win.top;
+        }
+        var tabBrowser;
+        try {
+            tabBrowser = getTabBrowser(
+                win.QueryInterface(Ci.nsIInterfaceRequestor).getInterface(Ci.nsIWebNavigation)
+                   .QueryInterface(Ci.nsIDocShell).rootTreeItem
+                   .QueryInterface(Ci.nsIInterfaceRequestor).getInterface(Ci.nsIDOMWindow)
+            );
+        } catch (ex) { }
+        if ( !tabBrowser ) {
+            return vAPI.noTabId;
+        }
+        if ( tabBrowser.getBrowserForContentWindow ) {
+            return tabWatcher.tabIdFromTarget(tabBrowser.getBrowserForContentWindow(win));
+        }
+        // Falling back onto _getTabForContentWindow to ensure older versions
+        // of Firefox work well.
+        return tabBrowser._getTabForContentWindow ?
+               tabWatcher.tabIdFromTarget(tabBrowser._getTabForContentWindow(win)) :
+               vAPI.noTabId;
+    },
+
+    rawtypeFromContentType: function(channel) {
+        var mime = channel.contentType;
+        if ( !mime ) {
+            return 0;
+        }
+        var pos = mime.indexOf('/');
+        if ( pos === -1 ) {
+            pos = mime.length;
+        }
+        return this.mimeTypeMap[mime.slice(0, pos)] || 0;
+    },
+
+    observe: function(channel, topic) {
+        if ( channel instanceof Ci.nsIHttpChannel === false ) {
+            return;
+        }
+
+        var URI = channel.URI;
+        var channelData = this.channelDataFromChannel(channel);
+
+        if ( topic.lastIndexOf('http-on-examine-', 0) === 0 ) {
+            if ( channelData === null ) {
+                return;
+            }
+
+            var type = this.frameTypeMap[channelData[1]];
+            if ( !type ) {
+                return;
+            }
+
+            topic = 'Content-Security-Policy';
+
+            var result;
+            try {
+                result = channel.getResponseHeader(topic);
+            } catch (ex) {
+                result = null;
+            }
+
+            result = vAPI.net.onHeadersReceived.callback({
+                parentFrameId: type === 'main_frame' ? -1 : 0,
+                responseHeaders: result ? [{name: topic, value: result}] : [],
+                tabId: channelData[0],
+                type: type,
+                url: URI.asciiSpec
+            });
+
+            if ( result ) {
+                channel.setResponseHeader(
+                    topic,
+                    result.responseHeaders.pop().value,
+                    true
+                );
+            }
+
+            return;
+        }
+
+        // http-on-modify-request
+
+        // The channel was previously serviced.
+        if ( channelData !== null ) {
+            this.handleRequest(channel, URI, channelData[0], channelData[1]);
+            return;
+        }
+
+        // The channel was never serviced.
+        var tabId;
+        var pendingRequest = this.lookupPendingRequest(URI.asciiSpec);
+        var rawType = 1;
+        var loadInfo = channel.loadInfo;
+
+        // https://github.com/gorhill/uMatrix/issues/390#issuecomment-155717004
+        if ( loadInfo ) {
+            rawType = loadInfo.externalContentPolicyType !== undefined ?
+                loadInfo.externalContentPolicyType :
+                loadInfo.contentPolicyType;
+            if ( !rawType ) {
+                rawType = 1;
+            }
+        }
+
+        if ( pendingRequest !== null ) {
+            tabId = pendingRequest.tabId;
+            // https://github.com/gorhill/uBlock/issues/654
+            // Use the request type from the HTTP observer point of view.
+            if ( rawType !== 1 ) {
+                pendingRequest.rawType = rawType;
+            } else {
+                rawType = pendingRequest.rawType;
+            }
+        } else {
+            tabId = this.tabIdFromChannel(channel);
+        }
+
+        if ( this.handleRequest(channel, URI, tabId, rawType) ) {
+            return;
+        }
+
+        if ( channel instanceof Ci.nsIWritablePropertyBag === false ) {
+            return;
+        }
+
+        // Carry data for behind-the-scene redirects
+        channel.setProperty(this.REQDATAKEY, [tabId, rawType]);
+    },
+
+    // contentPolicy.shouldLoad doesn't detect redirects, this needs to be used
+    asyncOnChannelRedirect: function(oldChannel, newChannel, flags, callback) {
+        // If error thrown, the redirect will fail
+        try {
+            var URI = newChannel.URI;
+            if ( !URI.schemeIs('http') && !URI.schemeIs('https') ) {
+                return;
+            }
+
+            if ( newChannel instanceof Ci.nsIWritablePropertyBag === false ) {
+                return;
+            }
+
+            var channelData = this.channelDataFromChannel(oldChannel);
+            if ( channelData === null ) {
+                return;
+            }
+
+            // Carry the data on in case of multiple redirects
+            newChannel.setProperty(this.REQDATAKEY, channelData);
+        } catch (ex) {
+            // console.error(ex);
+        } finally {
+            callback.onRedirectVerifyCallback(this.ACCEPT);
+        }
+    }
+};
+
+/******************************************************************************/
+
+vAPI.net = {};
+
+/******************************************************************************/
+
+vAPI.net.registerListeners = function() {
+    this.onBeforeRequest.types = this.onBeforeRequest.types ?
+        new Set(this.onBeforeRequest.types) :
+        null;
+    this.onBeforeSendHeaders.types = this.onBeforeSendHeaders.types ?
+        new Set(this.onBeforeSendHeaders.types) :
+        null;
+
+    var shouldLoadListenerMessageName = location.host + ':shouldLoad';
+    var shouldLoadListener = function(e) {
+        var details = e.data;
+        var pendingReq = httpObserver.createPendingRequest(details.url);
+        pendingReq.rawType = details.rawType;
+        pendingReq.tabId = tabWatcher.tabIdFromTarget(e.target);
+    };
+
+    // https://github.com/gorhill/uMatrix/issues/200
+    // We need this only for Firefox 34 and less: the tab id is derived from
+    // the origin of the message.
+    if ( !vAPI.modernFirefox ) {
+        vAPI.messaging.globalMessageManager.addMessageListener(
+            shouldLoadListenerMessageName,
+            shouldLoadListener
+        );
+    }
+
+    httpObserver.register();
+
+    cleanupTasks.push(function() {
+        if ( !vAPI.modernFirefox ) {
+            vAPI.messaging.globalMessageManager.removeMessageListener(
+                shouldLoadListenerMessageName,
+                shouldLoadListener
+            );
+        }
+
+        httpObserver.unregister();
+    });
+};
+
+/******************************************************************************/
+/******************************************************************************/
+
+vAPI.toolbarButton = {
+    id: location.host + '-button',
+    type: 'view',
+    viewId: location.host + '-panel',
+    label: vAPI.app.name,
+    tooltiptext: vAPI.app.name,
+    tabs: {/*tabId: {badge: 0, img: boolean}*/},
+    init: null,
+    codePath: ''
+};
+
+/******************************************************************************/
+
+// Non-Fennec: common code paths.
+
+(function() {
+    if ( vAPI.fennec ) {
+        return;
+    }
+
+    var tbb = vAPI.toolbarButton;
+    var popupCommittedWidth = 0;
+    var popupCommittedHeight = 0;
+
+    tbb.onViewShowing = function({target}) {
+        popupCommittedWidth = popupCommittedHeight = 0;
+        target.firstChild.setAttribute('src', vAPI.getURL('popup.html'));
+    };
+
+    tbb.onViewHiding = function({target}) {
+        target.parentNode.style.maxWidth = '';
+        target.firstChild.setAttribute('src', 'about:blank');
+    };
+
+    tbb.updateState = function(win, tabId) {
+        var button = win.document.getElementById(this.id);
+
+        if ( !button ) {
+            return;
+        }
+
+        var icon = this.tabs[tabId];
+        button.setAttribute('badge', icon && icon.badge || '');
+        button.classList.toggle('off', !icon || !icon.img);
+
+        var iconId = icon && icon.img ? icon.img : 'off';
+        icon = 'url(' + vAPI.getURL('img/browsericons/icon19-' + iconId + '.png') + ')';
+        button.style.listStyleImage = icon;
+    };
+
+    tbb.populatePanel = function(doc, panel) {
+        panel.setAttribute('id', this.viewId);
+
+        var iframe = doc.createElement('iframe');
+        iframe.setAttribute('type', 'content');
+
+        panel.appendChild(iframe);
+
+        var toPx = function(pixels) {
+            return pixels.toString() + 'px';
+        };
+
+        var scrollBarWidth = 0;
+        var resizeTimer = null;
+
+        var resizePopupDelayed = function(attempts) {
+            if ( resizeTimer !== null ) {
+                return false;
+            }
+
+            // Sanity check
+            attempts = (attempts || 0) + 1;
+            if ( attempts > 1/*000*/ ) {
+                //console.error('uMatrix> resizePopupDelayed: giving up after too many attempts');
+                return false;
+            }
+
+            resizeTimer = vAPI.setTimeout(resizePopup, 10, attempts);
+            return true;
+        };
+
+        var resizePopup = function(attempts) {
+            resizeTimer = null;
+
+            panel.parentNode.style.maxWidth = 'none';
+            var body = iframe.contentDocument.body;
+
+            // https://github.com/gorhill/uMatrix/issues/301
+            // Don't resize if committed size did not change.
+            if (
+                popupCommittedWidth === body.clientWidth &&
+                popupCommittedHeight === body.clientHeight
+            ) {
+                return;
+            }
+
+            // We set a limit for height
+            var height = Math.min(body.clientHeight, 600);
+
+            // https://github.com/chrisaljoudi/uBlock/issues/730
+            // Voodoo programming: this recipe works
+            panel.style.setProperty('height', toPx(height));
+            iframe.style.setProperty('height', toPx(height));
+
+            // Adjust width for presence/absence of vertical scroll bar which may
+            // have appeared as a result of last operation.
+            var contentWindow = iframe.contentWindow;
+            var width = body.clientWidth;
+            if ( contentWindow.scrollMaxY !== 0 ) {
+                width += scrollBarWidth;
+            }
+            panel.style.setProperty('width', toPx(width));
+
+            // scrollMaxX should always be zero once we know the scrollbar width
+            if ( contentWindow.scrollMaxX !== 0 ) {
+                scrollBarWidth = contentWindow.scrollMaxX;
+                width += scrollBarWidth;
+                panel.style.setProperty('width', toPx(width));
+            }
+
+            if ( iframe.clientHeight !== height || panel.clientWidth !== width ) {
+                if ( resizePopupDelayed(attempts) ) {
+                    return;
+                }
+                // resizePopupDelayed won't be called again, so commit
+                // dimentsions.
+            }
+
+            popupCommittedWidth = body.clientWidth;
+            popupCommittedHeight = body.clientHeight;
+        };
+
+        var onResizeRequested = function() {
+            var body = iframe.contentDocument.body;
+            if ( body.getAttribute('data-resize-popup') !== 'true' ) {
+                return;
+            }
+            body.removeAttribute('data-resize-popup');
+            resizePopupDelayed();
+        };
+
+        var onPopupReady = function() {
+            var win = this.contentWindow;
+
+            if ( !win || win.location.host !== location.host ) {
+                return;
+            }
+
+            if ( typeof tbb.onBeforePopupReady === 'function' ) {
+                tbb.onBeforePopupReady.call(this);
+            }
+
+            resizePopupDelayed();
+
+            var body = win.document.body;
+            body.removeAttribute('data-resize-popup');
+            var mutationObserver = new win.MutationObserver(onResizeRequested);
+            mutationObserver.observe(body, {
+                attributes: true,
+                attributeFilter: [ 'data-resize-popup' ]
+            });
+        };
+
+        iframe.addEventListener('load', onPopupReady, true);
+    };
+})();
+
+/******************************************************************************/
+
+// Firefox 28 and less
+
+(function() {
+    var tbb = vAPI.toolbarButton;
+    if ( tbb.init !== null ) {
+        return;
+    }
+    var CustomizableUI = null;
+    var forceLegacyToolbarButton = vAPI.localStorage.getBool('forceLegacyToolbarButton');
+    if ( !forceLegacyToolbarButton ) {
+        try {
+            CustomizableUI = Cu.import('resource:///modules/CustomizableUI.jsm', null).CustomizableUI;
+        } catch (ex) {
+        }
+    }
+    if ( CustomizableUI !== null ) {
+        return;
+    }
+
+    tbb.codePath = 'legacy';
+    tbb.id = 'umatrix-legacy-button';   // NOTE: must match legacy-toolbar-button.css
+    tbb.viewId = tbb.id + '-panel';
+
+    var styleSheetUri = null;
+
+    var createToolbarButton = function(window) {
+        var document = window.document;
+
+        var toolbarButton = document.createElement('toolbarbutton');
+        toolbarButton.setAttribute('id', tbb.id);
+        // type = panel would be more accurate, but doesn't look as good
+        toolbarButton.setAttribute('type', 'menu');
+        toolbarButton.setAttribute('removable', 'true');
+        toolbarButton.setAttribute('class', 'toolbarbutton-1 chromeclass-toolbar-additional');
+        toolbarButton.setAttribute('label', tbb.label);
+        toolbarButton.setAttribute('tooltiptext', tbb.label);
+
+        var toolbarButtonPanel = document.createElement('panel');
+        // NOTE: Setting level to parent breaks the popup for PaleMoon under
+        // linux (mouse pointer misaligned with content). For some reason.
+        // toolbarButtonPanel.setAttribute('level', 'parent');
+        tbb.populatePanel(document, toolbarButtonPanel);
+        toolbarButtonPanel.addEventListener('popupshowing', tbb.onViewShowing);
+        toolbarButtonPanel.addEventListener('popuphiding', tbb.onViewHiding);
+        toolbarButton.appendChild(toolbarButtonPanel);
+
+        return toolbarButton;
+    };
+
+    var addLegacyToolbarButton = function(window) {
+        // uMatrix's stylesheet lazily added.
+        if ( styleSheetUri === null ) {
+            var sss = Cc["@mozilla.org/content/style-sheet-service;1"]
+                        .getService(Ci.nsIStyleSheetService);
+            styleSheetUri = Services.io.newURI(vAPI.getURL("css/legacy-toolbar-button.css"), null, null);
+
+            // Register global so it works in all windows, including palette
+            if ( !sss.sheetRegistered(styleSheetUri, sss.AUTHOR_SHEET) ) {
+                sss.loadAndRegisterSheet(styleSheetUri, sss.AUTHOR_SHEET);
+            }
+        }
+
+        var document = window.document;
+
+        // https://github.com/gorhill/uMatrix/issues/357
+        // Already installed?
+        if ( document.getElementById(tbb.id) !== null ) {
+            return;
+        }
+
+        var toolbox = document.getElementById('navigator-toolbox') ||
+                      document.getElementById('mail-toolbox');
+        if ( toolbox === null ) {
+            return;
+        }
+
+        var toolbarButton = createToolbarButton(window);
+
+        // https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XUL/toolbarpalette
+        var palette = toolbox.palette;
+        if ( palette && palette.querySelector('#' + tbb.id) === null ) {
+            palette.appendChild(toolbarButton);
+        }
+
+        // Find the place to put the button.
+        // Pale Moon: `toolbox.externalToolbars` can be undefined. Seen while
+        //   testing popup test number 3:
+        //   http://raymondhill.net/ublock/popup.html
+        var toolbars = toolbox.externalToolbars ? toolbox.externalToolbars.slice() : [];
+        for ( var child of toolbox.children ) {
+            if ( child.localName === 'toolbar' ) {
+                toolbars.push(child);
+            }
+        }
+
+        for ( var toolbar of toolbars ) {
+            var currentsetString = toolbar.getAttribute('currentset');
+            if ( !currentsetString ) {
+                continue;
+            }
+            var currentset = currentsetString.split(/\s*,\s*/);
+            var index = currentset.indexOf(tbb.id);
+            if ( index === -1 ) {
+                continue;
+            }
+            // This can occur with Pale Moon:
+            //   "TypeError: toolbar.insertItem is not a function"
+            if ( typeof toolbar.insertItem !== 'function' ) {
+                continue;
+            }
+            // Found our button on this toolbar - but where on it?
+            var before = null;
+            for ( var i = index + 1; i < currentset.length; i++ ) {
+                before = toolbar.querySelector('[id="' + currentset[i] + '"]');
+                if ( before !== null ) {
+                    break;
+                }
+            }
+            // https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XUL/Method/insertItem
+            toolbar.insertItem(tbb.id, before);
+            break;
+        }
+
+        // https://github.com/gorhill/uBlock/issues/763
+        // We are done if our toolbar button is already installed in one of the
+        // toolbar.
+        if ( palette !== null && toolbarButton.parentElement !== palette ) {
+            return;
+        }
+
+        // No button yet so give it a default location. If forcing the button,
+        // just put in in the palette rather than on any specific toolbar (who
+        // knows what toolbars will be available or visible!)
+        var navbar = document.getElementById('nav-bar');
+        if ( navbar !== null && !vAPI.localStorage.getBool('legacyToolbarButtonAdded') ) {
+            // https://github.com/gorhill/uBlock/issues/264
+            // Find a child customizable palette, if any.
+            navbar = navbar.querySelector('.customization-target') || navbar;
+            navbar.appendChild(toolbarButton);
+            navbar.setAttribute('currentset', navbar.currentSet);
+            document.persist(navbar.id, 'currentset');
+            vAPI.localStorage.setBool('legacyToolbarButtonAdded', 'true');
+        }
+    };
+
+    var canAddLegacyToolbarButton = function(window) {
+        var document = window.document;
+        if (
+            !document ||
+            document.readyState !== 'complete' ||
+            document.getElementById('nav-bar') === null
+        ) {
+            return false;
+        }
+        var toolbox = document.getElementById('navigator-toolbox') ||
+                      document.getElementById('mail-toolbox');
+        return toolbox !== null && !!toolbox.palette;
+    };
+
+    var onPopupCloseRequested = function({target}) {
+        var document = target.ownerDocument;
+        if ( !document ) {
+            return;
+        }
+        var toolbarButtonPanel = document.getElementById(tbb.viewId);
+        if ( toolbarButtonPanel === null ) {
+            return;
+        }
+        // `hidePopup` reported as not existing while testing legacy button
+        //  on FF 41.0.2.
+        // https://bugzilla.mozilla.org/show_bug.cgi?id=1151796
+        if ( typeof toolbarButtonPanel.hidePopup === 'function' ) {
+            toolbarButtonPanel.hidePopup();
+        }
+    };
+
+    var shutdown = function() {
+        for ( var win of winWatcher.getWindows() ) {
+            var toolbarButton = win.document.getElementById(tbb.id);
+            if ( toolbarButton ) {
+                toolbarButton.parentNode.removeChild(toolbarButton);
+            }
+        }
+
+        if ( styleSheetUri !== null ) {
+            var sss = Cc["@mozilla.org/content/style-sheet-service;1"]
+                        .getService(Ci.nsIStyleSheetService);
+            if ( sss.sheetRegistered(styleSheetUri, sss.AUTHOR_SHEET) ) {
+                sss.unregisterSheet(styleSheetUri, sss.AUTHOR_SHEET);
+            }
+            styleSheetUri = null;
+        }
+
+        vAPI.messaging.globalMessageManager.removeMessageListener(
+            location.host + ':closePopup',
+            onPopupCloseRequested
+        );
+    };
+
+    tbb.attachToNewWindow = function(win) {
+        deferUntil(
+            canAddLegacyToolbarButton.bind(null, win),
+            addLegacyToolbarButton.bind(null, win)
+        );
+    };
+
+    tbb.init = function() {
+        vAPI.messaging.globalMessageManager.addMessageListener(
+            location.host + ':closePopup',
+            onPopupCloseRequested
+        );
+
+        cleanupTasks.push(shutdown);
+    };
+})();
+
+/******************************************************************************/
+
+// Firefox Australis < 36.
+
+(function() {
+    var tbb = vAPI.toolbarButton;
+    if ( tbb.init !== null ) {
+        return;
+    }
+    if ( Services.vc.compare(Services.appinfo.platformVersion, '36.0') >= 0 ) {
+        return null;
+    }
+    if ( vAPI.localStorage.getBool('forceLegacyToolbarButton') ) {
+        return null;
+    }
+    var CustomizableUI = null;
+    try {
+        CustomizableUI = Cu.import('resource:///modules/CustomizableUI.jsm', null).CustomizableUI;
+    } catch (ex) {
+    }
+    if ( CustomizableUI === null ) {
+        return;
+    }
+    tbb.codePath = 'australis';
+    tbb.CustomizableUI = CustomizableUI;
+    tbb.defaultArea = CustomizableUI.AREA_NAVBAR;
+
+    var styleURI = null;
+
+    var onPopupCloseRequested = function({target}) {
+        if ( typeof tbb.closePopup === 'function' ) {
+            tbb.closePopup(target);
+        }
+    };
+
+    var shutdown = function() {
+        CustomizableUI.destroyWidget(tbb.id);
+
+        for ( var win of winWatcher.getWindows() ) {
+            var panel = win.document.getElementById(tbb.viewId);
+            panel.parentNode.removeChild(panel);
+            win.QueryInterface(Ci.nsIInterfaceRequestor)
+               .getInterface(Ci.nsIDOMWindowUtils)
+               .removeSheet(styleURI, 1);
+        }
+
+        vAPI.messaging.globalMessageManager.removeMessageListener(
+            location.host + ':closePopup',
+            onPopupCloseRequested
+        );
+    };
+
+    tbb.onBeforeCreated = function(doc) {
+        var panel = doc.createElement('panelview');
+
+        this.populatePanel(doc, panel);
+
+        doc.getElementById('PanelUI-multiView').appendChild(panel);
+
+        doc.defaultView.QueryInterface(Ci.nsIInterfaceRequestor)
+            .getInterface(Ci.nsIDOMWindowUtils)
+            .loadSheet(styleURI, 1);
+    };
+
+    tbb.onBeforePopupReady = function() {
+        // https://github.com/gorhill/uBlock/issues/83
+        // Add `portrait` class if width is constrained.
+        try {
+            this.contentDocument.body.classList.toggle(
+                'portrait',
+                CustomizableUI.getWidget(tbb.id).areaType === CustomizableUI.TYPE_MENU_PANEL
+            );
+        } catch (ex) {
+            /* noop */
+        }
+    };
+
+    tbb.init = function() {
+        vAPI.messaging.globalMessageManager.addMessageListener(
+            location.host + ':closePopup',
+            onPopupCloseRequested
+        );
+
+        var style = [
+            '#' + this.id + '.off {',
+                'list-style-image: url(',
+                    vAPI.getURL('img/browsericons/icon19-off.png'),
+                ');',
+            '}',
+            '#' + this.id + ' {',
+                'list-style-image: url(',
+                    vAPI.getURL('img/browsericons/icon19.png'),
+                ');',
+            '}',
+            '#' + this.viewId + ', #' + this.viewId + ' > iframe {',
+                'width: 160px;',
+                'height: 290px;',
+                'overflow: hidden !important;',
+            '}',
+            '#' + this.id + '[badge]:not([badge=""])::after {',
+                'position: absolute;',
+                'margin-left: -16px;',
+                'margin-top: 3px;',
+                'padding: 1px 2px;',
+                'font-size: 9px;',
+                'font-weight: bold;',
+                'color: #fff;',
+                'background: #000;',
+                'content: attr(badge);',
+            '}'
+        ];
+
+        styleURI = Services.io.newURI(
+            'data:text/css,' + encodeURIComponent(style.join('')),
+            null,
+            null
+        );
+
+        this.closePopup = function(tabBrowser) {
+            CustomizableUI.hidePanelForNode(
+                tabBrowser.ownerDocument.getElementById(this.viewId)
+            );
+        };
+
+        CustomizableUI.createWidget(this);
+
+        cleanupTasks.push(shutdown);
+    };
+})();
+
+/******************************************************************************/
+
+// Firefox Australis >= 36.
+
+(function() {
+    var tbb = vAPI.toolbarButton;
+    if ( tbb.init !== null ) {
+        return;
+    }
+    if ( Services.vc.compare(Services.appinfo.platformVersion, '36.0') < 0 ) {
+        return null;
+    }
+    if ( vAPI.localStorage.getBool('forceLegacyToolbarButton') ) {
+        return null;
+    }
+    var CustomizableUI = null;
+    try {
+        CustomizableUI = Cu.import('resource:///modules/CustomizableUI.jsm', null).CustomizableUI;
+    } catch (ex) {
+    }
+    if ( CustomizableUI === null ) {
+        return null;
+    }
+    tbb.codePath = 'australis';
+    tbb.CustomizableUI = CustomizableUI;
+    tbb.defaultArea = CustomizableUI.AREA_NAVBAR;
+
+    var CUIEvents = {};
+
+    var badgeCSSRules = [
+        'background: #000',
+        'color: #fff'
+    ].join(';');
+
+    var updateBadgeStyle = function() {
+        for ( var win of winWatcher.getWindows() ) {
+            var button = win.document.getElementById(tbb.id);
+            if ( button === null ) {
+                continue;
+            }
+            var badge = button.ownerDocument.getAnonymousElementByAttribute(
+                button,
+                'class',
+                'toolbarbutton-badge'
+            );
+            if ( !badge ) {
+                continue;
+            }
+
+            badge.style.cssText = badgeCSSRules;
+        }
+    };
+
+    var updateBadge = function() {
+        var wId = tbb.id;
+        var buttonInPanel = CustomizableUI.getWidget(wId).areaType === CustomizableUI.TYPE_MENU_PANEL;
+
+        for ( var win of winWatcher.getWindows() ) {
+            var button = win.document.getElementById(wId);
+            if ( button === null ) {
+                continue;
+            }
+            if ( buttonInPanel ) {
+                button.classList.remove('badged-button');
+                continue;
+            }
+            button.classList.add('badged-button');
+        }
+
+        if ( buttonInPanel ) {
+            return;
+        }
+
+        // Anonymous elements need some time to be reachable
+        vAPI.setTimeout(updateBadgeStyle, 250);
+    }.bind(CUIEvents);
+
+    // https://developer.mozilla.org/en-US/docs/Mozilla/JavaScript_code_modules/CustomizableUI.jsm#Listeners
+    CUIEvents.onCustomizeEnd = updateBadge;
+    CUIEvents.onWidgetAdded = updateBadge;
+    CUIEvents.onWidgetUnderflow = updateBadge;
+
+    var onPopupCloseRequested = function({target}) {
+        if ( typeof tbb.closePopup === 'function' ) {
+            tbb.closePopup(target);
+        }
+    };
+
+    var shutdown = function() {
+        for ( var win of winWatcher.getWindows() ) {
+            var panel = win.document.getElementById(tbb.viewId);
+            if ( panel !== null && panel.parentNode !== null ) {
+                panel.parentNode.removeChild(panel);
+            }
+            win.QueryInterface(Ci.nsIInterfaceRequestor)
+                .getInterface(Ci.nsIDOMWindowUtils)
+                .removeSheet(styleURI, 1);
+        }
+
+        CustomizableUI.removeListener(CUIEvents);
+        CustomizableUI.destroyWidget(tbb.id);
+
+        vAPI.messaging.globalMessageManager.removeMessageListener(
+            location.host + ':closePopup',
+            onPopupCloseRequested
+        );
+    };
+
+    var styleURI = null;
+
+    tbb.onBeforeCreated = function(doc) {
+        var panel = doc.createElement('panelview');
+
+        this.populatePanel(doc, panel);
+
+        doc.getElementById('PanelUI-multiView').appendChild(panel);
+
+        doc.defaultView.QueryInterface(Ci.nsIInterfaceRequestor)
+            .getInterface(Ci.nsIDOMWindowUtils)
+            .loadSheet(styleURI, 1);
+    };
+
+    tbb.onCreated = function(button) {
+        button.setAttribute('badge', '');
+        vAPI.setTimeout(updateBadge, 250);
+    };
+
+    tbb.onBeforePopupReady = function() {
+        // https://github.com/gorhill/uBlock/issues/83
+        // Add `portrait` class if width is constrained.
+        try {
+            this.contentDocument.body.classList.toggle(
+                'portrait',
+                CustomizableUI.getWidget(tbb.id).areaType === CustomizableUI.TYPE_MENU_PANEL
+            );
+        } catch (ex) {
+            /* noop */
+        }
+    };
+
+    tbb.closePopup = function(tabBrowser) {
+        CustomizableUI.hidePanelForNode(
+            tabBrowser.ownerDocument.getElementById(tbb.viewId)
+        );
+    };
+
+    tbb.init = function() {
+        vAPI.messaging.globalMessageManager.addMessageListener(
+            location.host + ':closePopup',
+            onPopupCloseRequested
+        );
+
+        CustomizableUI.addListener(CUIEvents);
+
+        var style = [
+            '#' + this.id + '.off {',
+                'list-style-image: url(',
+                    vAPI.getURL('img/browsericons/icon19-off.png'),
+                ');',
+            '}',
+            '#' + this.id + ' {',
+                'list-style-image: url(',
+                    vAPI.getURL('img/browsericons/icon19-19.png'),
+                ');',
+            '}',
+            '#' + this.viewId + ', #' + this.viewId + ' > iframe {',
+                'height: 290px;',
+                'max-width: none !important;',
+                'min-width: 0 !important;',
+                'overflow: hidden !important;',
+                'padding: 0 !important;',
+                'width: 160px;',
+            '}'
+        ];
+
+        styleURI = Services.io.newURI(
+            'data:text/css,' + encodeURIComponent(style.join('')),
+            null,
+            null
+        );
+
+        CustomizableUI.createWidget(this);
+
+        cleanupTasks.push(shutdown);
+    };
+})();
+
+/******************************************************************************/
+
+// No toolbar button.
+
+(function() {
+    // Just to ensure the number of cleanup tasks is as expected: toolbar
+    // button code is one single cleanup task regardless of platform.
+    if ( vAPI.toolbarButton.init === null ) {
+        cleanupTasks.push(function(){});
+    }
+})();
+
+/******************************************************************************/
+
+if ( vAPI.toolbarButton.init !== null ) {
+    vAPI.toolbarButton.init();
+}
+
+/******************************************************************************/
+/******************************************************************************/
+
+vAPI.contextMenu = {
+    contextMap: {
+        frame: 'inFrame',
+        link: 'onLink',
+        image: 'onImage',
+        audio: 'onAudio',
+        video: 'onVideo',
+        editable: 'onEditableArea'
+    }
+};
+
+/******************************************************************************/
+
+vAPI.contextMenu.displayMenuItem = function({target}) {
+    var doc = target.ownerDocument;
+    var gContextMenu = doc.defaultView.gContextMenu;
+    if ( !gContextMenu.browser ) {
+        return;
+    }
+
+    var menuitem = doc.getElementById(vAPI.contextMenu.menuItemId);
+    var currentURI = gContextMenu.browser.currentURI;
+
+    // https://github.com/chrisaljoudi/uBlock/issues/105
+    // TODO: Should the element picker works on any kind of pages?
+    if ( !currentURI.schemeIs('http') && !currentURI.schemeIs('https') ) {
+        menuitem.setAttribute('hidden', true);
+        return;
+    }
+
+    var ctx = vAPI.contextMenu.contexts;
+
+    if ( !ctx ) {
+        menuitem.setAttribute('hidden', false);
+        return;
+    }
+
+    var ctxMap = vAPI.contextMenu.contextMap;
+
+    for ( var context of ctx ) {
+        if (
+            context === 'page' &&
+            !gContextMenu.onLink &&
+            !gContextMenu.onImage &&
+            !gContextMenu.onEditableArea &&
+            !gContextMenu.inFrame &&
+            !gContextMenu.onVideo &&
+            !gContextMenu.onAudio
+        ) {
+            menuitem.setAttribute('hidden', false);
+            return;
+        }
+
+        if (
+            ctxMap.hasOwnProperty(context) &&
+            gContextMenu[ctxMap[context]]
+        ) {
+            menuitem.setAttribute('hidden', false);
+            return;
+        }
+    }
+
+    menuitem.setAttribute('hidden', true);
+};
+
+/******************************************************************************/
+
+vAPI.contextMenu.register = (function() {
+    var register = function(doc) {
+        if ( !this.menuItemId ) {
+            return;
+        }
+
+        // Already installed?
+        if ( doc.getElementById(this.menuItemId) !== null ) {
+            return;
+        }
+
+        var contextMenu = doc.getElementById('contentAreaContextMenu');
+        var menuitem = doc.createElement('menuitem');
+        menuitem.setAttribute('id', this.menuItemId);
+        menuitem.setAttribute('label', this.menuLabel);
+        menuitem.setAttribute('image', vAPI.getURL('img/browsericons/icon19-19.png'));
+        menuitem.setAttribute('class', 'menuitem-iconic');
+        menuitem.addEventListener('command', this.onCommand);
+        contextMenu.addEventListener('popupshowing', this.displayMenuItem);
+        contextMenu.insertBefore(menuitem, doc.getElementById('inspect-separator'));
+    };
+
+    // https://github.com/gorhill/uBlock/issues/906
+    // Be sure document.readyState is 'complete': it could happen at launch
+    // time that we are called by vAPI.contextMenu.create() directly before
+    // the environment is properly initialized.
+    var registerSafely = function(doc, tryCount) {
+        if ( doc.readyState === 'complete' ) {
+            register.call(this, doc);
+            return;
+        }
+        if ( typeof tryCount !== 'number' ) {
+            tryCount = 0;
+        }
+        tryCount += 1;
+        if ( tryCount < 8 ) {
+            vAPI.setTimeout(registerSafely.bind(this, doc, tryCount), 200);
+        }
+    };
+
+    return registerSafely;
+})();
+
+/******************************************************************************/
+
+vAPI.contextMenu.unregister = function(doc) {
+    if ( !this.menuItemId ) {
+        return;
+    }
+
+    var menuitem = doc.getElementById(this.menuItemId);
+    if ( menuitem === null ) {
+        return;
+    }
+    var contextMenu = menuitem.parentNode;
+    menuitem.removeEventListener('command', this.onCommand);
+    contextMenu.removeEventListener('popupshowing', this.displayMenuItem);
+    contextMenu.removeChild(menuitem);
+};
+
+/******************************************************************************/
+
+vAPI.contextMenu.create = function(details, callback) {
+    this.menuItemId = details.id;
+    this.menuLabel = details.title;
+    this.contexts = details.contexts;
+
+    if ( Array.isArray(this.contexts) && this.contexts.length ) {
+        this.contexts = this.contexts.indexOf('all') === -1 ? this.contexts : null;
+    } else {
+        // default in Chrome
+        this.contexts = ['page'];
+    }
+
+    this.onCommand = function() {
+        var gContextMenu = getOwnerWindow(this).gContextMenu;
+        var details = {
+            menuItemId: this.id
+        };
+
+        if ( gContextMenu.inFrame ) {
+            details.tagName = 'iframe';
+            // Probably won't work with e10s
+            details.frameUrl = gContextMenu.focusedWindow.location.href;
+        } else if ( gContextMenu.onImage ) {
+            details.tagName = 'img';
+            details.srcUrl = gContextMenu.mediaURL;
+        } else if ( gContextMenu.onAudio ) {
+            details.tagName = 'audio';
+            details.srcUrl = gContextMenu.mediaURL;
+        } else if ( gContextMenu.onVideo ) {
+            details.tagName = 'video';
+            details.srcUrl = gContextMenu.mediaURL;
+        } else if ( gContextMenu.onLink ) {
+            details.tagName = 'a';
+            details.linkUrl = gContextMenu.linkURL;
+        }
+
+        callback(details, {
+            id: tabWatcher.tabIdFromTarget(gContextMenu.browser),
+            url: gContextMenu.browser.currentURI.asciiSpec
+        });
+    };
+
+    for ( var win of winWatcher.getWindows() ) {
+        this.register(win.document);
+    }
+};
+
+/******************************************************************************/
+
+vAPI.contextMenu.remove = function() {
+    for ( var win of winWatcher.getWindows() ) {
+        this.unregister(win.document);
+    }
+
+    this.menuItemId = null;
+    this.menuLabel = null;
+    this.contexts = null;
+    this.onCommand = null;
+};
+
+/******************************************************************************/
+/******************************************************************************/
+
+var optionsObserver = (function() {
+    var addonId = 'uMatrix@raymondhill.net';
+
+    var commandHandler = function() {
+        switch ( this.id ) {
+        case 'showDashboardButton':
+            vAPI.tabs.open({ url: 'dashboard.html', index: -1 });
+            break;
+        case 'showLoggerButton':
+            vAPI.tabs.open({ url: 'logger-ui.html', index: -1 });
+            break;
+        default:
+            break;
+        }
+    };
+
+    var setupOptionsButton = function(doc, id) {
+        var button = doc.getElementById(id);
+        if ( button === null ) {
+            return;
+        }
+        button.addEventListener('command', commandHandler);
+        button.label = vAPI.i18n(id);
+    };
+
+    var setupOptionsButtons = function(doc) {
+        setupOptionsButton(doc, 'showDashboardButton');
+        setupOptionsButton(doc, 'showLoggerButton');
+    };
+
+    var observer = {
+        observe: function(doc, topic, id) {
+            if ( id !== addonId ) {
+                return;
+            }
+
+            setupOptionsButtons(doc);
+        }
+    };
+
+    // https://github.com/gorhill/uBlock/issues/948
+    // Older versions of Firefox can throw here when looking up `currentURI`.
+
+    var canInit = function() {
+        try {
+            var tabBrowser = tabWatcher.currentBrowser();
+            return tabBrowser &&
+                   tabBrowser.currentURI &&
+                   tabBrowser.currentURI.spec === 'about:addons' &&
+                   tabBrowser.contentDocument &&
+                   tabBrowser.contentDocument.readyState === 'complete';
+        } catch (ex) {
+        }
+    };
+
+    // Manually add the buttons if the `about:addons` page is already opened.
+
+    var init = function() {
+        if ( canInit() ) {
+            setupOptionsButtons(tabWatcher.currentBrowser().contentDocument);
+        }
+    };
+
+    var unregister = function() {
+        Services.obs.removeObserver(observer, 'addon-options-displayed');
+    };
+
+    var register = function() {
+        Services.obs.addObserver(observer, 'addon-options-displayed', false);
+        cleanupTasks.push(unregister);
+        deferUntil(canInit, init, { next: 463 });
+    };
+
+    return {
+        register: register,
+        unregister: unregister
+    };
+})();
+
+optionsObserver.register();
+
+/******************************************************************************/
+/******************************************************************************/
+
+vAPI.lastError = function() {
+    return null;
+};
+
+/******************************************************************************/
+/******************************************************************************/
+
+// This is called only once, when everything has been loaded in memory after
+// the extension was launched. It can be used to inject content scripts
+// in already opened web pages, to remove whatever nuisance could make it to
+// the web pages before uBlock was ready.
+
+vAPI.onLoadAllCompleted = function() {
+    for ( var browser of tabWatcher.browsers() ) {
+        browser.messageManager.sendAsyncMessage(
+            location.host + '-load-completed'
+        );
+    }
+};
+
+/******************************************************************************/
+/******************************************************************************/
+
+// Likelihood is that we do not have to punycode: given punycode overhead,
+// it's faster to check and skip than do it unconditionally all the time.
+
+var punycodeHostname = punycode.toASCII;
+var isNotASCII = /[^\x21-\x7F]/;
+
+vAPI.punycodeHostname = function(hostname) {
+    return isNotASCII.test(hostname) ? punycodeHostname(hostname) : hostname;
+};
+
+vAPI.punycodeURL = function(url) {
+    if ( isNotASCII.test(url) ) {
+        return Services.io.newURI(url, null, null).asciiSpec;
+    }
+    return url;
+};
+
+/******************************************************************************/
+/******************************************************************************/
+
+vAPI.cloud = (function() {
+    var extensionBranchPath = 'extensions.' + location.host;
+    var cloudBranchPath = extensionBranchPath + '.cloudStorage';
+
+    // https://github.com/gorhill/uBlock/issues/80#issuecomment-132081658
+    //   We must use get/setComplexValue in order to properly handle strings
+    //   with unicode characters.
+    var iss = Ci.nsISupportsString;
+    var argstr = Components.classes['@mozilla.org/supports-string;1']
+                           .createInstance(iss);
+
+    var options = {
+        defaultDeviceName: '',
+        deviceName: ''
+    };
+
+    // User-supplied device name.
+    try {
+        options.deviceName = Services.prefs
+                                     .getBranch(extensionBranchPath + '.')
+                                     .getComplexValue('deviceName', iss)
+                                     .data;
+    } catch(ex) {
+    }
+
+    var getDefaultDeviceName = function() {
+        var name = '';
+        try {
+            name = Services.prefs
+                           .getBranch('services.sync.client.')
+                           .getComplexValue('name', iss)
+                           .data;
+        } catch(ex) {
+        }
+
+        return name || window.navigator.platform || window.navigator.oscpu;
+    };
+
+    var start = function(dataKeys) {
+        var extensionBranch = Services.prefs.getBranch(extensionBranchPath + '.');
+        var syncBranch = Services.prefs.getBranch('services.sync.prefs.sync.');
+
+        // Mark config entries as syncable
+        argstr.data = '';
+        var dataKey;
+        for ( var i = 0; i < dataKeys.length; i++ ) {
+            dataKey = dataKeys[i];
+            if ( extensionBranch.prefHasUserValue('cloudStorage.' + dataKey) === false ) {
+                extensionBranch.setComplexValue('cloudStorage.' + dataKey, iss, argstr);
+            }
+            syncBranch.setBoolPref(cloudBranchPath + '.' + dataKey, true);
+        }
+    };
+
+    var push = function(datakey, data, callback) {
+        var branch = Services.prefs.getBranch(cloudBranchPath + '.');
+        var bin = {
+            'source': options.deviceName || getDefaultDeviceName(),
+            'tstamp': Date.now(),
+            'data': data,
+            'size': 0
+        };
+        bin.size = JSON.stringify(bin).length;
+        argstr.data = JSON.stringify(bin);
+        branch.setComplexValue(datakey, iss, argstr);
+        if ( typeof callback === 'function' ) {
+            callback();
+        }
+    };
+
+    var pull = function(datakey, callback) {
+        var result = null;
+        var branch = Services.prefs.getBranch(cloudBranchPath + '.');
+        try {
+            var json = branch.getComplexValue(datakey, iss).data;
+            if ( typeof json === 'string' ) {
+                result = JSON.parse(json);
+            }
+        } catch(ex) {
+        }
+        callback(result);
+    };
+
+    var getOptions = function(callback) {
+        if ( typeof callback !== 'function' ) {
+            return;
+        }
+        options.defaultDeviceName = getDefaultDeviceName();
+        callback(options);
+    };
+
+    var setOptions = function(details, callback) {
+        if ( typeof details !== 'object' || details === null ) {
+            return;
+        }
+
+        var branch = Services.prefs.getBranch(extensionBranchPath + '.');
+
+        if ( typeof details.deviceName === 'string' ) {
+            argstr.data = details.deviceName;
+            branch.setComplexValue('deviceName', iss, argstr);
+            options.deviceName = details.deviceName;
+        }
+
+        getOptions(callback);
+    };
+
+    return {
+        start: start,
+        push: push,
+        pull: pull,
+        getOptions: getOptions,
+        setOptions: setOptions
+    };
+})();
+
+/******************************************************************************/
+/******************************************************************************/
+
+vAPI.browserData = {};
+
+/******************************************************************************/
+
+// https://developer.mozilla.org/en-US/docs/HTTP_Cache
+
+vAPI.browserData.clearCache = function(callback) {
+    // PURGE_DISK_DATA_ONLY:1
+    // PURGE_DISK_ALL:2
+    // PURGE_EVERYTHING:3
+    // However I verified that no argument does clear the cache data.
+    // There is no cache2 for older versions of Firefox.
+    if ( Services.cache2 ) {
+        Services.cache2.clear();
+    } else if ( Services.cache ) {
+        Services.cache.evictEntries(Services.cache.STORE_ON_DISK);
+    }
+    if ( typeof callback === 'function' ) {
+        callback();
+    }
+};
+
+/******************************************************************************/
+
+vAPI.browserData.clearOrigin = function(/* domain */) {
+    // TODO
+};
+
+/******************************************************************************/
+/******************************************************************************/
+
+// https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XPCOM/Reference/Interface/nsICookieManager2
+// https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XPCOM/Reference/Interface/nsICookie2
+// https://developer.mozilla.org/en-US/docs/Observer_Notifications#Cookies
+
+vAPI.cookies = {};
+
+/******************************************************************************/
+
+vAPI.cookies.CookieEntry = function(ffCookie) {
+    this.domain = ffCookie.host;
+    this.name = ffCookie.name;
+    this.path = ffCookie.path;
+    this.secure = ffCookie.isSecure === true;
+    this.session = ffCookie.expires === 0;
+    this.value = ffCookie.value;
+};
+
+/******************************************************************************/
+
+vAPI.cookies.start = function() {
+    Services.obs.addObserver(this, 'cookie-changed', false);
+    Services.obs.addObserver(this, 'private-cookie-changed', false);
+    cleanupTasks.push(this.stop.bind(this));
+};
+
+/******************************************************************************/
+
+vAPI.cookies.stop = function() {
+    Services.obs.removeObserver(this, 'cookie-changed');
+    Services.obs.removeObserver(this, 'private-cookie-changed');
+};
+
+/******************************************************************************/
+
+vAPI.cookies.observe = function(subject, topic, reason) {
+    //if ( topic !== 'cookie-changed' && topic !== 'private-cookie-changed' ) {
+    //    return;
+    //}
+    //
+    if ( reason === 'cleared' && typeof this.onAllRemoved === 'function' ) {
+        this.onAllRemoved();
+        return;
+    }
+    if ( subject === null ) {
+        return;
+    }
+    if ( subject instanceof Ci.nsICookie2 === false ) {
+        try {
+            subject = subject.QueryInterface(Ci.nsICookie2);
+        } catch (ex) {
+            return;
+        }
+    }
+    if ( reason === 'deleted' ) {
+        if ( typeof this.onRemoved === 'function' ) {
+            this.onRemoved(new this.CookieEntry(subject));
+        }
+        return;
+    }
+    if ( typeof this.onChanged === 'function' ) {
+        this.onChanged(new this.CookieEntry(subject));
+    }
+};
+
+/******************************************************************************/
+
+// Meant and expected to be asynchronous.
+
+vAPI.cookies.getAll = function(callback) {
+    if ( typeof callback !== 'function' ) {
+        return;
+    }
+    var onAsync = function() {
+        var out = [];
+        var enumerator = Services.cookies.enumerator;
+        var ffcookie;
+        while ( enumerator.hasMoreElements() ) {
+            ffcookie = enumerator.getNext();
+            if ( ffcookie instanceof Ci.nsICookie ) {
+                out.push(new this.CookieEntry(ffcookie));
+            }
+        }
+        callback(out);
+    };
+    vAPI.setTimeout(onAsync.bind(this), 0);
+};
+
+/******************************************************************************/
+
+vAPI.cookies.remove = function(details, callback) {
+    var uri = Services.io.newURI(details.url, null, null);
+    var cookies = Services.cookies;
+    cookies.remove(uri.asciiHost, details.name, uri.path, false, {});
+    cookies.remove( '.' + uri.asciiHost, details.name, uri.path, false, {});
+    if ( typeof callback === 'function' ) {
+        callback({
+            domain: uri.asciiHost,
+            name: details.name,
+            path: uri.path
+        });
+    }
+};
+
+/******************************************************************************/
+/******************************************************************************/
+
+})();
+
+/******************************************************************************/