diff --git a/Gruntfile.js b/Gruntfile.js
index a3b1251af..9f396ff45 100644
--- a/Gruntfile.js
+++ b/Gruntfile.js
@@ -83,7 +83,6 @@ module.exports = grunt => {
           'libtextsecure/helpers.js',
           'libtextsecure/stringview.js',
           'libtextsecure/event_target.js',
-          'libtextsecure/account_manager.js',
           'libtextsecure/http-resources.js',
           'libtextsecure/message_receiver.js',
           'libtextsecure/task_with_timeout.js',
diff --git a/js/background.js b/js/background.js
index 40d7af2a7..8ad8e0b88 100644
--- a/js/background.js
+++ b/js/background.js
@@ -96,27 +96,6 @@
   Whisper.events = _.clone(Backbone.Events);
   Whisper.events.isListenedTo = eventName =>
     Whisper.events._events ? !!Whisper.events._events[eventName] : false;
-  let accountManager;
-  window.getAccountManager = () => {
-    if (!accountManager) {
-      const USERNAME = storage.get('number_id');
-      const PASSWORD = storage.get('password');
-      accountManager = new textsecure.AccountManager(USERNAME, PASSWORD);
-      accountManager.addEventListener('registration', () => {
-        const user = {
-          ourNumber: libsession.Utils.UserUtils.getOurPubKeyStrFromCache(),
-          ourPrimary: window.textsecure.storage.get('primaryDevicePubKey'),
-        };
-        Whisper.events.trigger('userChanged', user);
-
-        Whisper.Registration.markDone();
-        window.log.info('dispatching registration event');
-        Whisper.events.trigger('registration_done');
-      });
-    }
-    return accountManager;
-  };
-
   const cancelInitializationMessage = Views.Initialization.setMessage();
 
   window.log.info('Storage fetch');
diff --git a/libtextsecure/account_manager.js b/libtextsecure/account_manager.js
deleted file mode 100644
index 9b1e30518..000000000
--- a/libtextsecure/account_manager.js
+++ /dev/null
@@ -1,162 +0,0 @@
-/* global
-  window,
-  textsecure,
-  libsignal,
-  mnemonic,
-  btoa,
-  getString,
-  Event,
-  dcodeIO,
-  StringView,
-  Event,
-*/
-
-/* eslint-disable more/no-then */
-/* eslint-disable no-unused-vars */
-/* eslint-disable no-await-in-loop */
-
-// eslint-disable-next-line func-names
-(function() {
-  window.textsecure = window.textsecure || {};
-
-  const ARCHIVE_AGE = 7 * 24 * 60 * 60 * 1000;
-
-  function AccountManager(username, password) {
-    this.pending = Promise.resolve();
-  }
-
-  function getNumber(numberId) {
-    if (!numberId || !numberId.length) {
-      return numberId;
-    }
-
-    const parts = numberId.split('.');
-    if (!parts.length) {
-      return numberId;
-    }
-
-    return parts[0];
-  }
-
-  AccountManager.prototype = new textsecure.EventTarget();
-  AccountManager.prototype.extend({
-    constructor: AccountManager,
-    registerSingleDevice(mnemonic, mnemonicLanguage, profileName) {
-      const createAccount = this.createAccount.bind(this);
-      const clearSessionsAndPreKeys = this.clearSessionsAndPreKeys.bind(this);
-      const registrationDone = this.registrationDone.bind(this);
-      let generateKeypair;
-      if (mnemonic) {
-        generateKeypair = () => {
-          let seedHex = window.mnemonic.mn_decode(mnemonic, mnemonicLanguage);
-          // handle shorter than 32 bytes seeds
-          const privKeyHexLength = 32 * 2;
-          if (seedHex.length !== privKeyHexLength) {
-            seedHex = seedHex.concat('0'.repeat(32));
-            seedHex = seedHex.substring(0, privKeyHexLength);
-          }
-          const seed = dcodeIO.ByteBuffer.wrap(seedHex, 'hex').toArrayBuffer();
-          return window.sessionGenerateKeyPair(seed);
-        };
-      } else {
-        generateKeypair = libsignal.KeyHelper.generateIdentityKeyPair;
-      }
-      return this.queueTask(() =>
-        generateKeypair().then(async identityKeyPair =>
-          createAccount(identityKeyPair)
-            .then(() => this.saveRecoveryPhrase(mnemonic))
-            .then(clearSessionsAndPreKeys)
-            .then(() => {
-              const pubKeyString = StringView.arrayBufferToHex(
-                identityKeyPair.pubKey
-              );
-              registrationDone(pubKeyString, profileName);
-            })
-        )
-      );
-    },
-    queueTask(task) {
-      const taskWithTimeout = textsecure.createTaskWithTimeout(task);
-      this.pending = this.pending.then(taskWithTimeout, taskWithTimeout);
-
-      return this.pending;
-    },
-    async createAccount(identityKeyPair, userAgent, readReceipts) {
-      let password = btoa(getString(libsignal.crypto.getRandomBytes(16)));
-      password = password.substring(0, password.length - 2);
-
-      await Promise.all([
-        textsecure.storage.remove('identityKey'),
-        textsecure.storage.remove('signaling_key'),
-        textsecure.storage.remove('password'),
-        textsecure.storage.remove('registrationId'),
-        textsecure.storage.remove('number_id'),
-        textsecure.storage.remove('device_name'),
-        textsecure.storage.remove('userAgent'),
-        textsecure.storage.remove('read-receipt-setting'),
-        textsecure.storage.remove('typing-indicators-setting'),
-        textsecure.storage.remove('regionCode'),
-      ]);
-
-      // update our own identity key, which may have changed
-      // if we're relinking after a reinstall on the master device
-      const pubKeyString = StringView.arrayBufferToHex(identityKeyPair.pubKey);
-
-      await textsecure.storage.put('identityKey', identityKeyPair);
-      await textsecure.storage.put('password', password);
-      if (userAgent) {
-        await textsecure.storage.put('userAgent', userAgent);
-      }
-
-      await textsecure.storage.put(
-        'read-receipt-setting',
-        Boolean(readReceipts)
-      );
-
-      // Enable typing indicators by default
-      await textsecure.storage.put('typing-indicators-setting', Boolean(true));
-
-      await textsecure.storage.user.setNumberAndDeviceId(pubKeyString, 1);
-    },
-    async clearSessionsAndPreKeys() {
-      window.log.info('clearing all sessions');
-      // During secondary device registration we need to keep our prekeys sent
-      // to other pubkeys
-      await Promise.all([
-        window.Signal.Data.removeAllPreKeys(),
-        window.Signal.Data.removeAllSignedPreKeys(),
-        window.Signal.Data.removeAllContactPreKeys(),
-        window.Signal.Data.removeAllContactSignedPreKeys(),
-        window.Signal.Data.removeAllSessions(),
-      ]);
-    },
-    async generateMnemonic(language = 'english') {
-      // Note: 4 bytes are converted into 3 seed words, so length 12 seed words
-      // (13 - 1 checksum) are generated using 12 * 4 / 3 = 16 bytes.
-      const seedSize = 16;
-      const seed = window.Signal.Crypto.getRandomBytes(seedSize);
-      const hex = StringView.arrayBufferToHex(seed);
-      return mnemonic.mn_encode(hex, language);
-    },
-    getCurrentRecoveryPhrase() {
-      return textsecure.storage.get('mnemonic');
-    },
-    saveRecoveryPhrase(mnemonic) {
-      return textsecure.storage.put('mnemonic', mnemonic);
-    },
-    async registrationDone(number, displayName) {
-      window.log.info('registration done');
-
-      textsecure.storage.put('primaryDevicePubKey', number);
-
-      // Ensure that we always have a conversation for ourself
-      const conversation = await window
-        .getConversationController()
-        .getOrCreateAndWait(number, 'private');
-      await conversation.setLokiProfile({ displayName });
-
-      this.dispatchEvent(new Event('registration'));
-    },
-  });
-  textsecure.AccountManager = AccountManager;
-})();
diff --git a/libtextsecure/test/index.html b/libtextsecure/test/index.html
index 32b53b28a..5c65e59bb 100644
--- a/libtextsecure/test/index.html
+++ b/libtextsecure/test/index.html
@@ -5,6 +5,7 @@
   <title>libtextsecure test runner</title>
   <link rel="stylesheet" href="../../node_modules/mocha/mocha.css" />
 </head>
+
 <body>
 
   <div id="mocha">
@@ -25,13 +26,11 @@
   <script type="text/javascript" src="../event_target.js" data-cover></script>
   <script type="text/javascript" src="../helpers.js" data-cover></script>
   <script type="text/javascript" src="../stringview.js" data-cover></script>
-  <script type="text/javascript" src="../account_manager.js" data-cover></script>
   <script type="text/javascript" src="../task_with_timeout.js" data-cover></script>
 
   <script type="text/javascript" src="errors_test.js"></script>
   <script type="text/javascript" src="helpers_test.js"></script>
   <script type="text/javascript" src="task_with_timeout_test.js"></script>
-  <script type="text/javascript" src="account_manager_test.js"></script>
 
   <!-- Comment out to turn off code coverage. Useful for getting real callstacks. -->
   <!--   NOTE: blanket doesn't support modern syntax and will choke until we find a replacement. :0( -->
@@ -42,4 +41,5 @@
     mocha.run();
   </script>
 </body>
-</html>
+
+</html>
\ No newline at end of file
diff --git a/preload.js b/preload.js
index 8361e58ee..fcad8abaf 100644
--- a/preload.js
+++ b/preload.js
@@ -86,7 +86,7 @@ window.isBeforeVersion = (toCheck, baseVersion) => {
 };
 
 // eslint-disable-next-line func-names
-window.CONSTANTS = new (function() {
+window.CONSTANTS = new (function () {
   this.MAX_GROUP_NAME_LENGTH = 64;
   this.DEFAULT_PUBLIC_CHAT_URL = appConfig.get('defaultPublicChatServer');
   this.MAX_LINKED_DEVICES = 1;
@@ -184,6 +184,7 @@ window.libsession = require('./ts/session');
 window.getConversationController =
   window.libsession.Conversations.ConversationController.getInstance;
 
+
 // We never do these in our code, so we'll prevent it everywhere
 window.open = () => null;
 // eslint-disable-next-line no-eval, no-multi-assign
@@ -377,7 +378,7 @@ window.callWorker = (fnName, ...args) => utilWorker.callWorker(fnName, ...args);
 
 // Linux seems to periodically let the event loop stop, so this is a global workaround
 setInterval(() => {
-  window.nodeSetImmediate(() => {});
+  window.nodeSetImmediate(() => { });
 }, 1000);
 
 const { autoOrientImage } = require('./js/modules/auto_orient_image');
@@ -458,9 +459,9 @@ if (process.env.USE_STUBBED_NETWORK) {
 }
 
 // eslint-disable-next-line no-extend-native,func-names
-Promise.prototype.ignore = function() {
+Promise.prototype.ignore = function () {
   // eslint-disable-next-line more/no-then
-  this.then(() => {});
+  this.then(() => { });
 };
 
 if (
diff --git a/ts/components/session/ActionsPanel.tsx b/ts/components/session/ActionsPanel.tsx
index 1292fcc0d..34a24ea8d 100644
--- a/ts/components/session/ActionsPanel.tsx
+++ b/ts/components/session/ActionsPanel.tsx
@@ -14,13 +14,13 @@ import { getTheme } from '../../state/selectors/theme';
 import { getOurNumber } from '../../state/selectors/user';
 import { UserUtils } from '../../session/utils';
 import {
-  forceSyncConfigurationNowIfNeeded,
   syncConfigurationIfNeeded,
 } from '../../session/utils/syncUtils';
 import { DAYS } from '../../session/utils/Number';
 import { removeItemById } from '../../data/data';
 import { OnionPaths } from '../../session/onions';
 import { getMessageQueue } from '../../session/sending';
+import { AccountManager } from '../../util';
 // tslint:disable-next-line: no-import-side-effect no-submodule-imports
 
 export enum SectionType {
@@ -77,7 +77,7 @@ class ActionsPanelPrivate extends React.Component<Props> {
     void this.showResetSessionIDDialogIfNeeded();
 
     // remove existing prekeys, sign prekeys and sessions
-    void window.getAccountManager().clearSessionsAndPreKeys();
+    void AccountManager.clearSessionsAndPreKeys();
 
     // trigger a sync message if needed for our other devices
     void syncConfigurationIfNeeded();
diff --git a/ts/components/session/SessionSeedModal.tsx b/ts/components/session/SessionSeedModal.tsx
index 5963652ef..c5e2ae7d7 100644
--- a/ts/components/session/SessionSeedModal.tsx
+++ b/ts/components/session/SessionSeedModal.tsx
@@ -2,7 +2,7 @@ import React from 'react';
 
 import { SessionModal } from './SessionModal';
 import { SessionButton } from './SessionButton';
-import { ToastUtils } from '../../session/utils';
+import { ToastUtils, UserUtils } from '../../session/utils';
 import { DefaultTheme, withTheme } from 'styled-components';
 import { PasswordUtil } from '../../util';
 import { getPasswordHash } from '../../data/data';
@@ -70,8 +70,8 @@ class SessionSeedModalInner extends React.Component<Props, State> {
             {hasPassword && !passwordValid ? (
               <>{this.renderPasswordView()}</>
             ) : (
-              <>{this.renderSeedView()}</>
-            )}
+                <>{this.renderSeedView()}</>
+              )}
           </SessionModal>
         )}
       </>
@@ -192,8 +192,7 @@ class SessionSeedModalInner extends React.Component<Props, State> {
       return false;
     }
 
-    const manager = await window.getAccountManager();
-    const recoveryPhrase = manager.getCurrentRecoveryPhrase();
+    const recoveryPhrase = UserUtils.getCurrentRecoveryPhrase();
 
     this.setState({
       recoveryPhrase,
diff --git a/ts/components/session/registration/RegistrationTabs.tsx b/ts/components/session/registration/RegistrationTabs.tsx
index b50c49662..b24441bc7 100644
--- a/ts/components/session/registration/RegistrationTabs.tsx
+++ b/ts/components/session/registration/RegistrationTabs.tsx
@@ -8,6 +8,7 @@ import { SignInTab } from './SignInTab';
 import { TabLabel, TabType } from './TabLabel';
 import { PasswordUtil } from '../../../util';
 import { trigger } from '../../../shims/events';
+import { AccountManager } from '../../../util/accountManager';
 
 export const MAX_USERNAME_LENGTH = 20;
 // tslint:disable: use-simple-attributes
@@ -70,7 +71,7 @@ export async function signUp(signUpDetails: {
     verifyPassword,
     generatedRecoveryPhrase,
   } = signUpDetails;
-  window.log.info('starting Signing up');
+  window.log.info('SIGNING UP');
   const trimName = displayName.trim();
 
   if (!trimName) {
@@ -103,9 +104,77 @@ export async function signUp(signUpDetails: {
     await resetRegistration();
     await window.setPassword(password);
     UserUtils.setRestoringFromSeed(false);
-    await window
-      .getAccountManager()
-      .registerSingleDevice(generatedRecoveryPhrase, 'english', trimName);
+    await AccountManager.registerSingleDevice(
+      generatedRecoveryPhrase,
+      'english',
+      trimName
+    );
+    await UserUtils.setLastProfileUpdateTimestamp(Date.now());
+    trigger('openInbox');
+  } catch (e) {
+    ToastUtils.pushToastError(
+      'registrationError',
+      `Error: ${e.message || 'Something went wrong'}`
+    );
+    window.log.warn('exception during registration:', e);
+  }
+}
+
+/**
+ * Sign in/restore from seed.
+ * Ask for a display name, as we will drop incoming ConfigurationMessages if any are saved on the swarm.
+ * We will handle a ConfigurationMessage
+ */
+export async function restoreFromSeed(signInDetails: {
+  displayName: string;
+  userRecoveryPhrase: string;
+  password: string;
+  verifyPassword: string;
+}) {
+  const {
+    displayName,
+    password,
+    verifyPassword,
+    userRecoveryPhrase,
+  } = signInDetails;
+  window.log.info('RESTORING FROM SEED');
+  const trimName = displayName.trim();
+
+  if (!trimName) {
+    window.log.warn('invalid trimmed name for registration');
+    ToastUtils.pushToastError(
+      'invalidDisplayName',
+      window.i18n('displayNameEmpty')
+    );
+    return;
+  }
+  const passwordErrors = validatePassword(password, verifyPassword);
+  if (passwordErrors.passwordErrorString) {
+    window.log.warn('invalid password for registration');
+    ToastUtils.pushToastError(
+      'invalidPassword',
+      window.i18n('invalidPassword')
+    );
+    return;
+  }
+  if (!!password && !passwordErrors.passwordFieldsMatch) {
+    window.log.warn('passwords does not match for registration');
+    ToastUtils.pushToastError(
+      'invalidPassword',
+      window.i18n('passwordsDoNotMatch')
+    );
+    return;
+  }
+
+  try {
+    await resetRegistration();
+    await window.setPassword(password);
+    UserUtils.setRestoringFromSeed(false);
+    await AccountManager.registerSingleDevice(
+      userRecoveryPhrase,
+      'english',
+      trimName
+    );
     await UserUtils.setLastProfileUpdateTimestamp(Date.now());
     trigger('openInbox');
   } catch (e) {
@@ -157,9 +226,7 @@ export class RegistrationTabs extends React.Component<any, State> {
   private async generateMnemonicAndKeyPair() {
     if (this.state.generatedRecoveryPhrase === '') {
       const language = 'english';
-      const mnemonic = await window
-        .getAccountManager()
-        .generateMnemonic(language);
+      const mnemonic = await AccountManager.generateMnemonic(language);
 
       let seedHex = window.mnemonic.mn_decode(mnemonic, language);
       // handle shorter than 32 bytes seeds
@@ -206,58 +273,48 @@ export class RegistrationTabs extends React.Component<any, State> {
     return <SignInTab />;
   }
 
-  private async register() {
-    // const {
-    //   password,
-    //   recoveryPhrase,
-    //   generatedRecoveryPhrase,
-    //   signInMode,
-    //   displayName,
-    //   passwordErrorString,
-    //   passwordFieldsMatch,
-    // } = this.state;
-    // if (signInMode === SignInMode.UsingRecoveryPhrase && !recoveryPhrase) {
-    //   window.log.warn('empty mnemonic seed passed in seed restoration mode');
-    //   return;
-    // } else if (!generatedRecoveryPhrase) {
-    //   window.log.warn('empty generated seed');
-    //   return;
-    // }
-    // const seedToUse =
-    //   signInMode === SignInMode.UsingRecoveryPhrase
-    //     ? recoveryPhrase
-    //     : generatedRecoveryPhrase;
-    // try {
-    //   await this.resetRegistration();
-    //   await window.setPassword(password);
-    //   const isRestoringFromSeed = signInMode === SignInMode.UsingRecoveryPhrase;
-    //   UserUtils.setRestoringFromSeed(isRestoringFromSeed);
-    //   await window
-    //     .getAccountManager()
-    //     .registerSingleDevice(seedToUse, 'english', trimName);
-    //   // if we are just creating a new account, no need to wait for a configuration message
-    //   if (!isRestoringFromSeed) {
-    //     trigger('openInbox');
-    //   } else {
-    //     // We have to pull for all messages of the user of this menmonic
-    //     // We are looking for the most recent ConfigurationMessage he sent to himself.
-    //     // When we find it, we can just get the displayName, avatar and groups saved in it.
-    //     // If we do not find one, we will need to ask for a display name.
-    //     window.log.warn('isRestoringFromSeed');
-    //   }
-    // } catch (e) {
-    //   ToastUtils.pushToastError(
-    //     'registrationError',
-    //     `Error: ${e.message || 'Something went wrong'}`
-    //   );
-    //   let exmsg = '';
-    //   if (e.message) {
-    //     exmsg += e.message;
-    //   }
-    //   if (e.stack) {
-    //     exmsg += ` | stack:  + ${e.stack}`;
-    //   }
-    //   window.log.warn('exception during registration:', exmsg);
-    // }
-  }
+  // private async register() {
+  //   const {
+  //     password,
+  //     recoveryPhrase,
+  //     generatedRecoveryPhrase,
+  //     signInMode,
+  //     displayName,
+  //     passwordErrorString,
+  //     passwordFieldsMatch,
+  //   } = this.state;
+  //   if (signInMode === SignInMode.UsingRecoveryPhrase && !recoveryPhrase) {
+  //     window.log.warn('empty mnemonic seed passed in seed restoration mode');
+  //     return;
+  //   } else if (!generatedRecoveryPhrase) {
+  //     window.log.warn('empty generated seed');
+  //     return;
+  //   }
+  //   const seedToUse =
+  //     signInMode === SignInMode.UsingRecoveryPhrase
+  //       ? recoveryPhrase
+  //       : generatedRecoveryPhrase;
+  //   try {
+  //     await this.resetRegistration();
+  //     await window.setPassword(password);
+  //     const isRestoringFromSeed = signInMode === SignInMode.UsingRecoveryPhrase;
+  //     UserUtils.setRestoringFromSeed(isRestoringFromSeed);
+  //     await AccountManager.registerSingleDevice(seedToUse, 'english', trimName);
+  //     // if we are just creating a new account, no need to wait for a configuration message
+  //     if (!isRestoringFromSeed) {
+  //       trigger('openInbox');
+  //     } else {
+  //       // We have to pull for all messages of the user of this menmonic
+  //       // We are looking for the most recent ConfigurationMessage he sent to himself.
+  //       // When we find it, we can just get the displayName, avatar and groups saved in it.
+  //       // If we do not find one, we will need to ask for a display name.
+  //       window.log.warn('isRestoringFromSeed');
+  //     }
+  //   } catch (e) {
+  //     ToastUtils.pushToastError(
+  //       'registrationError',
+  //       `Error: ${e.message || 'Something went wrong'}`
+  //     );
+  //   }
+  // }
 }
diff --git a/ts/data/data.ts b/ts/data/data.ts
index 1a702c655..8785c7412 100644
--- a/ts/data/data.ts
+++ b/ts/data/data.ts
@@ -556,7 +556,10 @@ export async function getConversationById(
   id: string
 ): Promise<ConversationModel | undefined> {
   const data = await channels.getConversationById(id);
-  return new ConversationModel(data);
+  if (data) {
+    return new ConversationModel(data);
+  }
+  return undefined;
 }
 
 export async function updateConversation(
diff --git a/ts/session/utils/User.ts b/ts/session/utils/User.ts
index 5c0d35e8a..c3bc4420d 100644
--- a/ts/session/utils/User.ts
+++ b/ts/session/utils/User.ts
@@ -115,3 +115,11 @@ export function setLastProfileUpdateTimestamp(lastUpdateTimestamp: number) {
     lastUpdateTimestamp
   );
 }
+
+export function getCurrentRecoveryPhrase() {
+  return window.textsecure.storage.get('mnemonic');
+}
+
+export function saveRecoveryPhrase(mnemonic: string) {
+  return window.textsecure.storage.put('mnemonic', mnemonic);
+}
diff --git a/ts/util/accountManager.ts b/ts/util/accountManager.ts
new file mode 100644
index 000000000..0c61c2b3a
--- /dev/null
+++ b/ts/util/accountManager.ts
@@ -0,0 +1,135 @@
+import { ConversationController } from '../session/conversations';
+import { getSodium } from '../session/crypto';
+import { UserUtils } from '../session/utils';
+import {
+  fromArrayBufferToBase64,
+  fromHex,
+  toHex,
+} from '../session/utils/String';
+import { getOurPubKeyStrFromCache } from '../session/utils/User';
+import { trigger } from '../shims/events';
+
+const generateKeypair = async (mnemonic: string, mnemonicLanguage: string) => {
+  let seedHex = window.mnemonic.mn_decode(mnemonic, mnemonicLanguage);
+  // handle shorter than 32 bytes seeds
+  const privKeyHexLength = 32 * 2;
+  if (seedHex.length !== privKeyHexLength) {
+    seedHex = seedHex.concat('0'.repeat(32));
+    seedHex = seedHex.substring(0, privKeyHexLength);
+  }
+  const seed = fromHex(seedHex);
+  console.warn('generateKeypair seedHex', seedHex);
+  console.warn('generateKeypair seed', seed);
+  return window.sessionGenerateKeyPair(seed);
+};
+
+// TODO not sure why AccountManager was a singleton before. Can we get rid of it as a singleton?
+// tslint:disable-next-line: no-unnecessary-class
+export class AccountManager {
+  public static async registerSingleDevice(
+    mnemonic: string,
+    mnemonicLanguage: string,
+    profileName: string
+  ) {
+    const createAccount = this.createAccount.bind(this);
+    const clearSessionsAndPreKeys = this.clearSessionsAndPreKeys.bind(this);
+    const registrationDone = this.registrationDone.bind(this);
+    if (!mnemonic) {
+      throw new Error(
+        'Session always needs a mnemonic. Either generated or given by the user'
+      );
+    }
+    if (!profileName) {
+      throw new Error('We always needs a profileName');
+    }
+    if (!mnemonicLanguage) {
+      throw new Error('We always needs a mnemonicLanguage');
+    }
+
+    const identityKeyPair = await generateKeypair(mnemonic, mnemonicLanguage);
+    await createAccount(identityKeyPair);
+    UserUtils.saveRecoveryPhrase(mnemonic);
+    await clearSessionsAndPreKeys();
+    const pubKeyString = toHex(identityKeyPair.pubKey);
+    await registrationDone(pubKeyString, profileName);
+  }
+
+  public static async generateMnemonic(language = 'english') {
+    // Note: 4 bytes are converted into 3 seed words, so length 12 seed words
+    // (13 - 1 checksum) are generated using 12 * 4 / 3 = 16 bytes.
+    const seedSize = 16;
+    const seed = window.Signal.Crypto.getRandomBytes(seedSize);
+    const hex = toHex(seed);
+    return window.mnemonic.mn_encode(hex, language);
+  }
+
+  public static async clearSessionsAndPreKeys() {
+    window.log.info('clearing all sessions');
+    // During secondary device registration we need to keep our prekeys sent
+    // to other pubkeys
+    await Promise.all([
+      window.Signal.Data.removeAllPreKeys(),
+      window.Signal.Data.removeAllSignedPreKeys(),
+      window.Signal.Data.removeAllContactPreKeys(),
+      window.Signal.Data.removeAllContactSignedPreKeys(),
+      window.Signal.Data.removeAllSessions(),
+    ]);
+  }
+
+  private static async createAccount(identityKeyPair: any) {
+    const sodium = await getSodium();
+    let password = fromArrayBufferToBase64(sodium.randombytes_buf(16));
+    password = password.substring(0, password.length - 2);
+
+    await Promise.all([
+      window.textsecure.storage.remove('identityKey'),
+      window.textsecure.storage.remove('signaling_key'),
+      window.textsecure.storage.remove('password'),
+      window.textsecure.storage.remove('registrationId'),
+      window.textsecure.storage.remove('number_id'),
+      window.textsecure.storage.remove('device_name'),
+      window.textsecure.storage.remove('userAgent'),
+      window.textsecure.storage.remove('read-receipt-setting'),
+      window.textsecure.storage.remove('typing-indicators-setting'),
+      window.textsecure.storage.remove('regionCode'),
+    ]);
+
+    // update our own identity key, which may have changed
+    // if we're relinking after a reinstall on the master device
+    const pubKeyString = toHex(identityKeyPair.pubKey);
+
+    await window.textsecure.storage.put('identityKey', identityKeyPair);
+    await window.textsecure.storage.put('password', password);
+    await window.textsecure.storage.put('read-receipt-setting', false);
+
+    // Enable typing indicators by default
+    await window.textsecure.storage.put(
+      'typing-indicators-setting',
+      Boolean(true)
+    );
+
+    await window.textsecure.storage.user.setNumberAndDeviceId(pubKeyString, 1);
+  }
+
+  private static async registrationDone(number: string, displayName: string) {
+    window.log.info('registration done');
+
+    window.textsecure.storage.put('primaryDevicePubKey', number);
+
+    // Ensure that we always have a conversation for ourself
+    const conversation = await ConversationController.getInstance().getOrCreateAndWait(
+      number,
+      'private'
+    );
+    await conversation.setLokiProfile({ displayName });
+    const user = {
+      ourNumber: getOurPubKeyStrFromCache(),
+      ourPrimary: window.textsecure.storage.get('primaryDevicePubKey'),
+    };
+    trigger('userChanged', user);
+
+    window.Whisper.Registration.markDone();
+    window.log.info('dispatching registration event');
+    trigger('registration_done');
+  }
+}
diff --git a/ts/util/index.ts b/ts/util/index.ts
index 214a13908..c8ce097ea 100644
--- a/ts/util/index.ts
+++ b/ts/util/index.ts
@@ -10,6 +10,7 @@ import * as AttachmentUtil from './attachmentsUtil';
 import * as LinkPreviewUtil from './linkPreviewFetch';
 
 export * from './blockedNumberController';
+export * from './accountManager';
 
 export {
   arrayBufferToObjectURL,
diff --git a/ts/window.d.ts b/ts/window.d.ts
index 5cd849f31..4a58a76b9 100644
--- a/ts/window.d.ts
+++ b/ts/window.d.ts
@@ -49,7 +49,6 @@ declare global {
     deleteAccount: any;
     displayNameRegex: any;
     friends: any;
-    getAccountManager: any;
     getConversations: any;
     getFriendsFromContacts: any;
     getSettingValue: any;