Adding upstream version 124.0.1.upstream/124.0.1

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

11 files changed, 878 insertions, 0 deletions

diff --git a/devtools/client/aboutdebugging/src/modules/client-wrapper.js b/devtools/client/aboutdebugging/src/modules/client-wrapper.js
new file mode 100644
index 0000000000..6d537b60a4
--- /dev/null
+++ b/devtools/client/aboutdebugging/src/modules/client-wrapper.js
@@ -0,0 +1,217 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const {
+  checkVersionCompatibility,
+} = require("resource://devtools/client/shared/remote-debugging/version-checker.js");
+
+const {
+  RUNTIME_PREFERENCE,
+} = require("resource://devtools/client/aboutdebugging/src/constants.js");
+const {
+  WorkersListener,
+} = require("resource://devtools/client/shared/workers-listener.js");
+const RootResourceCommand = require("resource://devtools/shared/commands/root-resource/root-resource-command.js");
+
+const PREF_TYPES = {
+  BOOL: "BOOL",
+};
+
+// Map of preference to preference type.
+const PREF_TO_TYPE = {
+  [RUNTIME_PREFERENCE.CHROME_DEBUG_ENABLED]: PREF_TYPES.BOOL,
+  [RUNTIME_PREFERENCE.CONNECTION_PROMPT]: PREF_TYPES.BOOL,
+  [RUNTIME_PREFERENCE.PERMANENT_PRIVATE_BROWSING]: PREF_TYPES.BOOL,
+  [RUNTIME_PREFERENCE.REMOTE_DEBUG_ENABLED]: PREF_TYPES.BOOL,
+  [RUNTIME_PREFERENCE.SERVICE_WORKERS_ENABLED]: PREF_TYPES.BOOL,
+};
+
+// Some events are fired by mainRoot rather than client.
+const MAIN_ROOT_EVENTS = ["addonListChanged", "tabListChanged"];
+
+/**
+ * The ClientWrapper class is used to isolate aboutdebugging from the DevTools client API
+ * The modules of about:debugging should never call DevTools client APIs directly.
+ */
+class ClientWrapper {
+  constructor(client) {
+    this.client = client;
+    this.workersListener = new WorkersListener(client.mainRoot);
+  }
+
+  once(evt, listener) {
+    if (MAIN_ROOT_EVENTS.includes(evt)) {
+      this.client.mainRoot.once(evt, listener);
+    } else {
+      this.client.once(evt, listener);
+    }
+  }
+
+  on(evt, listener) {
+    if (evt === "workersUpdated") {
+      this.workersListener.addListener(listener);
+    } else if (MAIN_ROOT_EVENTS.includes(evt)) {
+      this.client.mainRoot.on(evt, listener);
+    } else {
+      this.client.on(evt, listener);
+    }
+  }
+
+  off(evt, listener) {
+    if (evt === "workersUpdated") {
+      this.workersListener.removeListener(listener);
+    } else if (MAIN_ROOT_EVENTS.includes(evt)) {
+      this.client.mainRoot.off(evt, listener);
+    } else {
+      this.client.off(evt, listener);
+    }
+  }
+
+  async getFront(typeName) {
+    return this.client.mainRoot.getFront(typeName);
+  }
+
+  async getDeviceDescription() {
+    const deviceFront = await this.getFront("device");
+    const description = await deviceFront.getDescription();
+
+    // Only expose a specific set of properties.
+    return {
+      canDebugServiceWorkers: description.canDebugServiceWorkers,
+      channel: description.channel,
+      deviceName: description.deviceName,
+      name: description.brandName,
+      os: description.os,
+      version: description.version,
+    };
+  }
+
+  createRootResourceCommand() {
+    return new RootResourceCommand({ rootFront: this.client.mainRoot });
+  }
+
+  async checkVersionCompatibility() {
+    return checkVersionCompatibility(this.client);
+  }
+
+  async setPreference(prefName, value) {
+    const prefType = PREF_TO_TYPE[prefName];
+    const preferenceFront = await this.client.mainRoot.getFront("preference");
+    switch (prefType) {
+      case PREF_TYPES.BOOL:
+        return preferenceFront.setBoolPref(prefName, value);
+      default:
+        throw new Error("Unsupported preference" + prefName);
+    }
+  }
+
+  async getPreference(prefName, defaultValue) {
+    if (typeof defaultValue === "undefined") {
+      throw new Error(
+        "Default value is mandatory for getPreference, the actor will " +
+          "throw if the preference is not set on the target runtime"
+      );
+    }
+
+    const prefType = PREF_TO_TYPE[prefName];
+    const preferenceFront = await this.client.mainRoot.getFront("preference");
+    switch (prefType) {
+      case PREF_TYPES.BOOL:
+        // TODO: Add server-side trait and methods to pass a default value to getBoolPref.
+        // See Bug 1522588.
+        let prefValue;
+        try {
+          prefValue = await preferenceFront.getBoolPref(prefName);
+        } catch (e) {
+          prefValue = defaultValue;
+        }
+        return prefValue;
+      default:
+        throw new Error("Unsupported preference:" + prefName);
+    }
+  }
+
+  async listTabs() {
+    return this.client.mainRoot.listTabs();
+  }
+
+  async listAddons(options) {
+    return this.client.mainRoot.listAddons(options);
+  }
+
+  async getAddon({ id }) {
+    return this.client.mainRoot.getAddon({ id });
+  }
+
+  async uninstallAddon({ id }) {
+    const addonsFront = await this.getFront("addons");
+    return addonsFront.uninstallAddon(id);
+  }
+
+  async getMainProcess() {
+    return this.client.mainRoot.getMainProcess();
+  }
+
+  async getServiceWorkerFront({ id }) {
+    return this.client.mainRoot.getWorker(id);
+  }
+
+  async listWorkers() {
+    const { other, service, shared } =
+      await this.client.mainRoot.listAllWorkers();
+
+    return {
+      otherWorkers: other,
+      serviceWorkers: service,
+      sharedWorkers: shared,
+    };
+  }
+
+  async close() {
+    return this.client.close();
+  }
+
+  isClosed() {
+    return this.client._transportClosed;
+  }
+
+  // This method will be mocked to return a dummy URL during mochitests
+  getPerformancePanelUrl() {
+    return "chrome://devtools/content/performance-new/panel/index.xhtml";
+  }
+
+  /**
+   * @param {Window} win - The window of the dialog window.
+   * @param {Function} openAboutProfiling
+   */
+  async loadPerformanceProfiler(win, openAboutProfiling) {
+    const perfFront = await this.getFront("perf");
+    const { traits } = this.client;
+    await win.gInit(perfFront, traits, "devtools-remote", openAboutProfiling);
+  }
+
+  /**
+   * @param {Window} win - The window of the dialog window.
+   * @param {Function} openRemoteDevTools
+   */
+  async loadAboutProfiling(win, openRemoteDevTools) {
+    const perfFront = await this.getFront("perf");
+    const isSupportedPlatform = await perfFront.isSupportedPlatform();
+    const supportedFeatures = await perfFront.getSupportedFeatures();
+    await win.gInit(
+      "aboutprofiling-remote",
+      isSupportedPlatform,
+      supportedFeatures,
+      openRemoteDevTools
+    );
+  }
+
+  get traits() {
+    return { ...this.client.mainRoot.traits };
+  }
+}
+
+exports.ClientWrapper = ClientWrapper;
diff --git a/devtools/client/aboutdebugging/src/modules/debug-target-collapsibilities.js b/devtools/client/aboutdebugging/src/modules/debug-target-collapsibilities.js
new file mode 100644
index 0000000000..efba47e03a
--- /dev/null
+++ b/devtools/client/aboutdebugging/src/modules/debug-target-collapsibilities.js
@@ -0,0 +1,46 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const PREF_PREFIX = "devtools.aboutdebugging.collapsibilities.";
+const {
+  DEBUG_TARGET_PANE,
+} = require("resource://devtools/client/aboutdebugging/src/constants.js");
+
+/**
+ * This module provides a collection of helper methods to read and update the debug
+ * target pane's collapsibilities.
+ */
+
+/**
+ * @return {Object}
+ *         {
+ *           key: constants.DEBUG_TARGET_PANE
+ *           value: true - collapsed
+ *                  false - expanded
+ *         }
+ */
+function getDebugTargetCollapsibilities() {
+  const map = new Map();
+
+  for (const key of Object.values(DEBUG_TARGET_PANE)) {
+    const pref = Services.prefs.getBoolPref(PREF_PREFIX + key, false);
+    map.set(key, pref);
+  }
+
+  return map;
+}
+exports.getDebugTargetCollapsibilities = getDebugTargetCollapsibilities;
+
+/**
+ * @param collapsibilities - Same format to getDebugTargetCollapsibilities.
+ */
+function setDebugTargetCollapsibilities(collapsibilities) {
+  for (const key of Object.values(DEBUG_TARGET_PANE)) {
+    const isCollapsed = collapsibilities.get(key);
+    Services.prefs.setBoolPref(PREF_PREFIX + key, isCollapsed);
+  }
+}
+exports.setDebugTargetCollapsibilities = setDebugTargetCollapsibilities;
diff --git a/devtools/client/aboutdebugging/src/modules/debug-target-support.js b/devtools/client/aboutdebugging/src/modules/debug-target-support.js
new file mode 100644
index 0000000000..2b8d4afa5b
--- /dev/null
+++ b/devtools/client/aboutdebugging/src/modules/debug-target-support.js
@@ -0,0 +1,98 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const {
+  DEBUG_TARGET_PANE,
+  PREFERENCES,
+  RUNTIMES,
+} = require("resource://devtools/client/aboutdebugging/src/constants.js");
+
+// Process target debugging is disabled by default.
+function isProcessDebuggingSupported() {
+  return Services.prefs.getBoolPref(
+    PREFERENCES.PROCESS_DEBUGGING_ENABLED,
+    false
+  );
+}
+
+// Local tab debugging is disabled by default.
+function isLocalTabDebuggingSupported() {
+  return Services.prefs.getBoolPref(
+    PREFERENCES.LOCAL_TAB_DEBUGGING_ENABLED,
+    false
+  );
+}
+
+// Local process debugging is disabled by default.
+// This preference has no default value in
+// devtools/client/preferences/devtools-client.js
+// because it is only intended for tests.
+function isLocalProcessDebuggingSupported() {
+  return Services.prefs.getBoolPref(
+    "devtools.aboutdebugging.test-local-process-debugging",
+    false
+  );
+}
+
+// Installing extensions can be disabled in enterprise policy.
+// Note: Temporary Extensions are only supported when debugging This Firefox, so checking
+// the local preference is acceptable here. If we enable Temporary extensions for remote
+// runtimes, we should retrieve the preference from the target runtime instead.
+function isTemporaryExtensionSupported() {
+  return Services.prefs.getBoolPref(PREFERENCES.XPINSTALL_ENABLED, true);
+}
+
+const ALL_DEBUG_TARGET_PANES = [
+  DEBUG_TARGET_PANE.INSTALLED_EXTENSION,
+  ...(isProcessDebuggingSupported() ? [DEBUG_TARGET_PANE.PROCESSES] : []),
+  DEBUG_TARGET_PANE.OTHER_WORKER,
+  DEBUG_TARGET_PANE.SERVICE_WORKER,
+  DEBUG_TARGET_PANE.SHARED_WORKER,
+  DEBUG_TARGET_PANE.TAB,
+  ...(isTemporaryExtensionSupported()
+    ? [DEBUG_TARGET_PANE.TEMPORARY_EXTENSION]
+    : []),
+];
+
+// All debug target panes (to filter out if any of the panels should be excluded).
+const REMOTE_DEBUG_TARGET_PANES = [...ALL_DEBUG_TARGET_PANES];
+
+const THIS_FIREFOX_DEBUG_TARGET_PANES = ALL_DEBUG_TARGET_PANES
+  // Main process debugging is not available for This Firefox.
+  // At the moment only the main process is listed under processes, so remove the category
+  // for this runtime.
+  .filter(
+    p => p !== DEBUG_TARGET_PANE.PROCESSES || isLocalProcessDebuggingSupported()
+  )
+  // Showing tab targets for This Firefox is behind a preference.
+  .filter(p => p !== DEBUG_TARGET_PANE.TAB || isLocalTabDebuggingSupported());
+
+const SUPPORTED_TARGET_PANE_BY_RUNTIME = {
+  [RUNTIMES.THIS_FIREFOX]: THIS_FIREFOX_DEBUG_TARGET_PANES,
+  [RUNTIMES.USB]: REMOTE_DEBUG_TARGET_PANES,
+  [RUNTIMES.NETWORK]: REMOTE_DEBUG_TARGET_PANES,
+};
+
+/**
+ * A debug target pane is more specialized than a debug target. For instance EXTENSION is
+ * a DEBUG_TARGET but INSTALLED_EXTENSION and TEMPORARY_EXTENSION are DEBUG_TARGET_PANES.
+ */
+function isSupportedDebugTargetPane(runtimeType, debugTargetPaneKey) {
+  return SUPPORTED_TARGET_PANE_BY_RUNTIME[runtimeType].includes(
+    debugTargetPaneKey
+  );
+}
+exports.isSupportedDebugTargetPane = isSupportedDebugTargetPane;
+
+/**
+ * Check if the given runtimeType supports temporary extension installation
+ * from about:debugging (currently disallowed on non-local runtimes).
+ */
+function supportsTemporaryExtensionInstaller(runtimeType) {
+  return runtimeType === RUNTIMES.THIS_FIREFOX;
+}
+exports.supportsTemporaryExtensionInstaller =
+  supportsTemporaryExtensionInstaller;
diff --git a/devtools/client/aboutdebugging/src/modules/extensions-helper.js b/devtools/client/aboutdebugging/src/modules/extensions-helper.js
new file mode 100644
index 0000000000..ec0d7c2661
--- /dev/null
+++ b/devtools/client/aboutdebugging/src/modules/extensions-helper.js
@@ -0,0 +1,92 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  FileUtils: "resource://gre/modules/FileUtils.sys.mjs",
+});
+
+const {
+  PREFERENCES,
+} = require("resource://devtools/client/aboutdebugging/src/constants.js");
+
+exports.parseFileUri = function (url) {
+  // Strip a leading slash from Windows drive letter URIs.
+  // file:///home/foo ~> /home/foo
+  // file:///C:/foo ~> C:/foo
+  const windowsRegex = /^file:\/\/\/([a-zA-Z]:\/.*)/;
+  if (windowsRegex.test(url)) {
+    return windowsRegex.exec(url)[1];
+  }
+  return url.slice("file://".length);
+};
+
+exports.getExtensionUuid = function (extension) {
+  const { manifestURL } = extension;
+  // Strip off the protocol and rest, leaving us with just the UUID.
+  return manifestURL ? /moz-extension:\/\/([^/]*)/.exec(manifestURL)[1] : null;
+};
+
+/**
+ * Open a file picker to allow the user to locate a temporary extension. A temporary
+ * extension can either be:
+ * - a folder
+ * - a .xpi file
+ * - a .zip file
+ *
+ * @param  {Window} win
+ *         The window object where the filepicker should be opened.
+ *         Note: We cannot use the global window object here because it is undefined if
+ *         this module is loaded from a file outside of devtools/client/aboutdebugging/.
+ *         See browser-loader.js `uri.startsWith(baseURI)` for more details.
+ * @param  {String} message
+ *         The help message that should be displayed to the user in the filepicker.
+ * @return {Promise} returns a promise that resolves a File object corresponding to the
+ *         file selected by the user.
+ */
+exports.openTemporaryExtension = function (win, message) {
+  return new Promise(resolve => {
+    const fp = Cc["@mozilla.org/filepicker;1"].createInstance(Ci.nsIFilePicker);
+    fp.init(win, message, Ci.nsIFilePicker.modeOpen);
+
+    // Try to set the last directory used as "displayDirectory".
+    try {
+      const lastDirPath = Services.prefs.getCharPref(
+        PREFERENCES.TEMPORARY_EXTENSION_PATH,
+        ""
+      );
+      const lastDir = new lazy.FileUtils.File(lastDirPath);
+      fp.displayDirectory = lastDir;
+    } catch (e) {
+      // Empty or invalid value, nothing to handle.
+    }
+
+    fp.open(res => {
+      if (res == Ci.nsIFilePicker.returnCancel || !fp.file) {
+        return;
+      }
+      let file = fp.file;
+      // AddonManager.installTemporaryAddon accepts either
+      // addon directory or final xpi file.
+      if (
+        !file.isDirectory() &&
+        !file.leafName.endsWith(".xpi") &&
+        !file.leafName.endsWith(".zip")
+      ) {
+        file = file.parent;
+      }
+
+      // We are about to resolve, store the path to the file for the next call.
+      Services.prefs.setCharPref(
+        PREFERENCES.TEMPORARY_EXTENSION_PATH,
+        file.path
+      );
+
+      resolve(file);
+    });
+  });
+};
diff --git a/devtools/client/aboutdebugging/src/modules/l10n.js b/devtools/client/aboutdebugging/src/modules/l10n.js
new file mode 100644
index 0000000000..88c7ae8bb1
--- /dev/null
+++ b/devtools/client/aboutdebugging/src/modules/l10n.js
@@ -0,0 +1,12 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const {
+  FluentL10n,
+} = require("resource://devtools/client/shared/fluent-l10n/fluent-l10n.js");
+
+// exports a singleton, which will be used across all aboutdebugging modules
+exports.l10n = new FluentL10n();
diff --git a/devtools/client/aboutdebugging/src/modules/moz.build b/devtools/client/aboutdebugging/src/modules/moz.build
new file mode 100644
index 0000000000..909e181714
--- /dev/null
+++ b/devtools/client/aboutdebugging/src/modules/moz.build
@@ -0,0 +1,16 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+DevToolsModules(
+    "client-wrapper.js",
+    "debug-target-collapsibilities.js",
+    "debug-target-support.js",
+    "extensions-helper.js",
+    "l10n.js",
+    "network-locations.js",
+    "runtime-client-factory.js",
+    "runtime-default-preferences.js",
+    "runtimes-state-helper.js",
+    "usb-runtimes.js",
+)
diff --git a/devtools/client/aboutdebugging/src/modules/network-locations.js b/devtools/client/aboutdebugging/src/modules/network-locations.js
new file mode 100644
index 0000000000..cbae436df7
--- /dev/null
+++ b/devtools/client/aboutdebugging/src/modules/network-locations.js
@@ -0,0 +1,69 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const NETWORK_LOCATIONS_PREF = "devtools.aboutdebugging.network-locations";
+
+/**
+ * This module provides a collection of helper methods to read and update network
+ * locations monitored by about-debugging.
+ */
+
+function addNetworkLocationsObserver(listener) {
+  Services.prefs.addObserver(NETWORK_LOCATIONS_PREF, listener);
+}
+exports.addNetworkLocationsObserver = addNetworkLocationsObserver;
+
+function removeNetworkLocationsObserver(listener) {
+  Services.prefs.removeObserver(NETWORK_LOCATIONS_PREF, listener);
+}
+exports.removeNetworkLocationsObserver = removeNetworkLocationsObserver;
+
+/**
+ * Read the current preference value for aboutdebugging network locations.
+ * Will throw if the value cannot be parsed or is not an array.
+ */
+function _parsePreferenceAsArray() {
+  const pref = Services.prefs.getStringPref(NETWORK_LOCATIONS_PREF, "[]");
+  const parsedValue = JSON.parse(pref);
+  if (!Array.isArray(parsedValue)) {
+    throw new Error("Expected array value in " + NETWORK_LOCATIONS_PREF);
+  }
+  return parsedValue;
+}
+
+function getNetworkLocations() {
+  try {
+    return _parsePreferenceAsArray();
+  } catch (e) {
+    Services.prefs.clearUserPref(NETWORK_LOCATIONS_PREF);
+    return [];
+  }
+}
+exports.getNetworkLocations = getNetworkLocations;
+
+function addNetworkLocation(location) {
+  const locations = getNetworkLocations();
+  const locationsSet = new Set(locations);
+  locationsSet.add(location);
+
+  Services.prefs.setStringPref(
+    NETWORK_LOCATIONS_PREF,
+    JSON.stringify([...locationsSet])
+  );
+}
+exports.addNetworkLocation = addNetworkLocation;
+
+function removeNetworkLocation(location) {
+  const locations = getNetworkLocations();
+  const locationsSet = new Set(locations);
+  locationsSet.delete(location);
+
+  Services.prefs.setStringPref(
+    NETWORK_LOCATIONS_PREF,
+    JSON.stringify([...locationsSet])
+  );
+}
+exports.removeNetworkLocation = removeNetworkLocation;
diff --git a/devtools/client/aboutdebugging/src/modules/runtime-client-factory.js b/devtools/client/aboutdebugging/src/modules/runtime-client-factory.js
new file mode 100644
index 0000000000..e553416c18
--- /dev/null
+++ b/devtools/client/aboutdebugging/src/modules/runtime-client-factory.js
@@ -0,0 +1,68 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const {
+  prepareTCPConnection,
+} = require("resource://devtools/client/shared/remote-debugging/adb/commands/index.js");
+const {
+  DevToolsClient,
+} = require("resource://devtools/client/devtools-client.js");
+const {
+  DevToolsServer,
+} = require("resource://devtools/server/devtools-server.js");
+const {
+  ClientWrapper,
+} = require("resource://devtools/client/aboutdebugging/src/modules/client-wrapper.js");
+const {
+  remoteClientManager,
+} = require("resource://devtools/client/shared/remote-debugging/remote-client-manager.js");
+
+const {
+  RUNTIMES,
+} = require("resource://devtools/client/aboutdebugging/src/constants.js");
+
+async function createLocalClient() {
+  DevToolsServer.init();
+  DevToolsServer.registerAllActors();
+  DevToolsServer.allowChromeProcess = true;
+
+  const client = new DevToolsClient(DevToolsServer.connectPipe());
+  await client.connect();
+  return new ClientWrapper(client);
+}
+
+async function createNetworkClient(host, port) {
+  const transport = await DevToolsClient.socketConnect({ host, port });
+  const client = new DevToolsClient(transport);
+  await client.connect();
+  return new ClientWrapper(client);
+}
+
+async function createUSBClient(deviceId, socketPath) {
+  const port = await prepareTCPConnection(deviceId, socketPath);
+  return createNetworkClient("localhost", port);
+}
+
+async function createClientForRuntime(runtime) {
+  const { extra, id, type } = runtime;
+
+  if (type === RUNTIMES.THIS_FIREFOX) {
+    return createLocalClient();
+  } else if (remoteClientManager.hasClient(id, type)) {
+    const client = remoteClientManager.getClient(id, type);
+    return new ClientWrapper(client);
+  } else if (type === RUNTIMES.NETWORK) {
+    const { host, port } = extra.connectionParameters;
+    return createNetworkClient(host, port);
+  } else if (type === RUNTIMES.USB) {
+    const { deviceId, socketPath } = extra.connectionParameters;
+    return createUSBClient(deviceId, socketPath);
+  }
+
+  return null;
+}
+
+exports.createClientForRuntime = createClientForRuntime;
diff --git a/devtools/client/aboutdebugging/src/modules/runtime-default-preferences.js b/devtools/client/aboutdebugging/src/modules/runtime-default-preferences.js
new file mode 100644
index 0000000000..02c06334f7
--- /dev/null
+++ b/devtools/client/aboutdebugging/src/modules/runtime-default-preferences.js
@@ -0,0 +1,101 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+/**
+ * This module provides a workaround for remote debugging when a preference is
+ * defined in the firefox preference file (browser/app/profile/firefox.js) but
+ * still read from the server, without any default value.
+ *
+ * This causes the server to crash and can't easily be recovered.
+ *
+ * While we work on better linting to prevent such issues (Bug 1660182), this
+ * module will be able to set default values for all missing preferences.
+ */
+
+const PREFERENCE_TYPES = {
+  BOOL: "BOOL",
+  CHAR: "CHAR",
+  INT: "INT",
+};
+exports.PREFERENCE_TYPES = PREFERENCE_TYPES;
+
+/**
+ * Expected properties for the preference descriptors:
+ * - prefName {String}: the name of the preference.
+ * - defaultValue {String|Bool|Number}: the value to set if the preference is
+ *   missing.
+ * - trait {String}: the name of the trait corresponding to this pref on the
+ *   PreferenceFront.
+ * - type {String}: the preference type (either BOOL, CHAR or INT).
+ */
+const DEFAULT_PREFERENCES = [];
+exports.DEFAULT_PREFERENCES = DEFAULT_PREFERENCES;
+
+const METHODS = {
+  [PREFERENCE_TYPES.BOOL]: {
+    setPref: "setBoolPref",
+    getPref: "getBoolPref",
+  },
+  [PREFERENCE_TYPES.CHAR]: {
+    setPref: "setCharPref",
+    getPref: "getCharPref",
+  },
+  [PREFERENCE_TYPES.INT]: {
+    setPref: "setIntPref",
+    getPref: "getIntPref",
+  },
+};
+
+/**
+ * Set default values for all the provided preferences on the runtime
+ * corresponding to the provided clientWrapper, if needed.
+ *
+ * Note: prefDescriptors will most likely be DEFAULT_PREFERENCES when
+ * used in production code, but can be parameterized for tests.
+ *
+ * @param {ClientWrapper} clientWrapper
+ * @param {Array} prefDescriptors
+ *        Array of preference descriptors, see DEFAULT_PREFERENCES.
+ */
+async function setDefaultPreferencesIfNeeded(clientWrapper, prefDescriptors) {
+  if (!prefDescriptors || prefDescriptors.length === 0) {
+    return;
+  }
+
+  const preferenceFront = await clientWrapper.getFront("preference");
+  const preferenceTraits = await preferenceFront.getTraits();
+
+  // Note: using Promise.all here fails because the request/responses get mixed.
+  for (const prefDescriptor of prefDescriptors) {
+    // If the fix for this preference is already on this server, skip it.
+    if (preferenceTraits[prefDescriptor.trait]) {
+      continue;
+    }
+
+    await setDefaultPreference(preferenceFront, prefDescriptor);
+  }
+}
+exports.setDefaultPreferencesIfNeeded = setDefaultPreferencesIfNeeded;
+
+async function setDefaultPreference(preferenceFront, prefDescriptor) {
+  const { prefName, type, defaultValue } = prefDescriptor;
+
+  if (!Object.values(PREFERENCE_TYPES).includes(type)) {
+    throw new Error(`Unsupported type for setDefaultPreference "${type}"`);
+  }
+
+  const prefMethods = METHODS[type];
+  try {
+    // Try to read the preference only to check if the call is successful.
+    // If not, this means the preference is missing and should be initialized.
+    await preferenceFront[prefMethods.getPref](prefName);
+  } catch (e) {
+    console.warn(
+      `Preference "${prefName}"" is not set on the remote runtime. Setting default value.`
+    );
+    await preferenceFront[prefMethods.setPref](prefName, defaultValue);
+  }
+}
diff --git a/devtools/client/aboutdebugging/src/modules/runtimes-state-helper.js b/devtools/client/aboutdebugging/src/modules/runtimes-state-helper.js
new file mode 100644
index 0000000000..1864ef8341
--- /dev/null
+++ b/devtools/client/aboutdebugging/src/modules/runtimes-state-helper.js
@@ -0,0 +1,37 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+function getCurrentRuntime(runtimesState) {
+  const selectedRuntimeId = runtimesState.selectedRuntimeId;
+  return findRuntimeById(selectedRuntimeId, runtimesState);
+}
+exports.getCurrentRuntime = getCurrentRuntime;
+
+function getCurrentClient(runtimesState) {
+  const runtimeDetails = getCurrentRuntimeDetails(runtimesState);
+  return runtimeDetails ? runtimeDetails.clientWrapper : null;
+}
+exports.getCurrentClient = getCurrentClient;
+
+function findRuntimeById(id, runtimesState) {
+  return getAllRuntimes(runtimesState).find(r => r.id === id);
+}
+exports.findRuntimeById = findRuntimeById;
+
+function getAllRuntimes(runtimesState) {
+  return [
+    ...runtimesState.networkRuntimes,
+    ...runtimesState.thisFirefoxRuntimes,
+    ...runtimesState.usbRuntimes,
+  ];
+}
+exports.getAllRuntimes = getAllRuntimes;
+
+function getCurrentRuntimeDetails(runtimesState) {
+  const runtime = getCurrentRuntime(runtimesState);
+  return runtime ? runtime.runtimeDetails : null;
+}
+exports.getCurrentRuntimeDetails = getCurrentRuntimeDetails;
diff --git a/devtools/client/aboutdebugging/src/modules/usb-runtimes.js b/devtools/client/aboutdebugging/src/modules/usb-runtimes.js
new file mode 100644
index 0000000000..887dc6788e
--- /dev/null
+++ b/devtools/client/aboutdebugging/src/modules/usb-runtimes.js
@@ -0,0 +1,122 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+loader.lazyRequireGetter(
+  this,
+  "adb",
+  "resource://devtools/client/shared/remote-debugging/adb/adb.js",
+  true
+);
+
+/**
+ * Used to represent a regular runtime returned by ADB.
+ */
+class UsbRuntime {
+  constructor(adbRuntime) {
+    this.id = adbRuntime.id;
+    this.deviceId = adbRuntime.deviceId;
+    this.deviceName = adbRuntime.deviceName;
+    this.shortName = adbRuntime.shortName;
+    this.socketPath = adbRuntime.socketPath;
+    this.isFenix = adbRuntime.isFenix;
+    this.isUnavailable = false;
+    this.isUnplugged = false;
+    this.versionName = adbRuntime.versionName;
+  }
+}
+
+/**
+ * Used when a device was detected, meaning USB debugging is enabled on the device, but no
+ * runtime/browser is available for connection.
+ */
+class UnavailableUsbRuntime {
+  constructor(adbDevice) {
+    this.id = adbDevice.id + "|unavailable";
+    this.deviceId = adbDevice.id;
+    this.deviceName = adbDevice.name;
+    this.shortName = "Unavailable runtime";
+    this.socketPath = null;
+    this.isFenix = false;
+    this.isUnavailable = true;
+    this.isUnplugged = false;
+    this.versionName = null;
+  }
+}
+
+/**
+ * Used to represent USB devices that were previously connected but are now missing
+ * (presumably after being unplugged/disconnected from the computer).
+ */
+class UnpluggedUsbRuntime {
+  constructor(deviceId, deviceName) {
+    this.id = deviceId + "|unplugged";
+    this.deviceId = deviceId;
+    this.deviceName = deviceName;
+    this.shortName = "Unplugged runtime";
+    this.socketPath = null;
+    this.isFenix = false;
+    this.isUnavailable = true;
+    this.isUnplugged = true;
+    this.versionName = null;
+  }
+}
+
+/**
+ * Map used to keep track of discovered usb devices. Will be used to create the unplugged
+ * usb runtimes.
+ */
+const devices = new Map();
+
+/**
+ * This module provides a collection of helper methods to detect USB runtimes whom Firefox
+ * is running on.
+ */
+function addUSBRuntimesObserver(listener) {
+  adb.registerListener(listener);
+}
+exports.addUSBRuntimesObserver = addUSBRuntimesObserver;
+
+async function getUSBRuntimes() {
+  // Get the available runtimes
+  const runtimes = adb.getRuntimes().map(r => new UsbRuntime(r));
+
+  // Get devices found by ADB, but without any available runtime.
+  const runtimeDevices = runtimes.map(r => r.deviceId);
+  const unavailableRuntimes = adb
+    .getDevices()
+    .filter(d => !runtimeDevices.includes(d.id))
+    .map(d => new UnavailableUsbRuntime(d));
+
+  // Add all devices to the map detected devices.
+  const allRuntimes = runtimes.concat(unavailableRuntimes);
+  for (const runtime of allRuntimes) {
+    devices.set(runtime.deviceId, runtime.deviceName);
+  }
+
+  // Get devices previously found by ADB but no longer available.
+  const currentDevices = allRuntimes.map(r => r.deviceId);
+  const detectedDevices = [...devices.keys()];
+  const unpluggedDevices = detectedDevices.filter(
+    id => !currentDevices.includes(id)
+  );
+  const unpluggedRuntimes = unpluggedDevices.map(deviceId => {
+    const deviceName = devices.get(deviceId);
+    return new UnpluggedUsbRuntime(deviceId, deviceName);
+  });
+
+  return allRuntimes.concat(unpluggedRuntimes);
+}
+exports.getUSBRuntimes = getUSBRuntimes;
+
+function removeUSBRuntimesObserver(listener) {
+  adb.unregisterListener(listener);
+}
+exports.removeUSBRuntimesObserver = removeUSBRuntimesObserver;
+
+function refreshUSBRuntimes() {
+  return adb.updateRuntimes();
+}
+exports.refreshUSBRuntimes = refreshUSBRuntimes;