diff --git a/src/components/structures/EmbeddedPage.js b/src/components/structures/EmbeddedPage.js
index cbfeff7582..c37ab3df48 100644
--- a/src/components/structures/EmbeddedPage.js
+++ b/src/components/structures/EmbeddedPage.js
@@ -16,8 +16,6 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-'use strict';
-
 import React from 'react';
 import PropTypes from 'prop-types';
 import request from 'browser-request';
diff --git a/src/components/views/auth/AuthBody.js b/src/components/views/auth/AuthBody.js
index 9a078efb52..7881486a5f 100644
--- a/src/components/views/auth/AuthBody.js
+++ b/src/components/views/auth/AuthBody.js
@@ -14,8 +14,6 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-'use strict';
-
 import React from 'react';
 
 export default class AuthBody extends React.PureComponent {
diff --git a/src/components/views/auth/AuthHeaderLogo.js b/src/components/views/auth/AuthHeaderLogo.js
index 9edf149a83..2f27885322 100644
--- a/src/components/views/auth/AuthHeaderLogo.js
+++ b/src/components/views/auth/AuthHeaderLogo.js
@@ -14,8 +14,6 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-'use strict';
-
 import React from 'react';
 
 export default class AuthHeaderLogo extends React.PureComponent {
diff --git a/src/components/views/auth/CompleteSecurityBody.js b/src/components/views/auth/CompleteSecurityBody.js
index d757de9fe0..734af3192c 100644
--- a/src/components/views/auth/CompleteSecurityBody.js
+++ b/src/components/views/auth/CompleteSecurityBody.js
@@ -14,8 +14,6 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-'use strict';
-
 import React from 'react';
 
 export default class CompleteSecurityBody extends React.PureComponent {
diff --git a/src/components/views/elements/Flair.js b/src/components/views/elements/Flair.js
index 0f06904b68..645444b300 100644
--- a/src/components/views/elements/Flair.js
+++ b/src/components/views/elements/Flair.js
@@ -14,8 +14,6 @@
  limitations under the License.
  */
 
-'use strict';
-
 import React from 'react';
 import PropTypes from 'prop-types';
 import FlairStore from '../../../stores/FlairStore';
diff --git a/src/components/views/messages/MAudioBody.js b/src/components/views/messages/MAudioBody.js
index 587dee4513..ac42b485d7 100644
--- a/src/components/views/messages/MAudioBody.js
+++ b/src/components/views/messages/MAudioBody.js
@@ -14,8 +14,6 @@
  limitations under the License.
  */
 
-'use strict';
-
 import React from 'react';
 import MFileBody from './MFileBody';
 
diff --git a/src/notifications/VectorPushRulesDefinitions.js b/src/notifications/VectorPushRulesDefinitions.js
index 98d197a004..c049a81c15 100644
--- a/src/notifications/VectorPushRulesDefinitions.js
+++ b/src/notifications/VectorPushRulesDefinitions.js
@@ -15,8 +15,6 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-'use strict';
-
 import { _td } from '../languageHandler';
 import {StandardActions} from "./StandardActions";
 import {PushRuleVectorState} from "./PushRuleVectorState";
diff --git a/src/notifications/index.js b/src/notifications/index.js
index 7c400ad8b3..96c176303b 100644
--- a/src/notifications/index.js
+++ b/src/notifications/index.js
@@ -15,8 +15,6 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-'use strict';
-
 export * from "./NotificationUtils";
 export * from "./PushRuleVectorState";
 export * from "./VectorPushRulesDefinitions";
diff --git a/src/utils/MegolmExportEncryption.js b/src/utils/MegolmExportEncryption.js
index cde20a0eb2..be7472901a 100644
--- a/src/utils/MegolmExportEncryption.js
+++ b/src/utils/MegolmExportEncryption.js
@@ -15,8 +15,6 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-"use strict";
-
 // polyfill textencoder if necessary
 import * as TextEncodingUtf8 from 'text-encoding-utf-8';
 let TextEncoder = window.TextEncoder;
diff --git a/test/test-utils.js b/test/test-utils.js
index 839e1d6cd8..b6e0468d86 100644
--- a/test/test-utils.js
+++ b/test/test-utils.js
@@ -1,5 +1,3 @@
-"use strict";
-
 import React from 'react';
 import {MatrixClientPeg as peg} from '../src/MatrixClientPeg';
 import dis from '../src/dispatcher/dispatcher';
diff --git a/test/utils/MegolmExportEncryption-test.js b/test/utils/MegolmExportEncryption-test.js
index 1fd305b0a6..e0ed5ba26a 100644
--- a/test/utils/MegolmExportEncryption-test.js
+++ b/test/utils/MegolmExportEncryption-test.js
@@ -14,8 +14,6 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-"use strict";
-
 import {TextEncoder} from "util";
 import nodeCrypto from "crypto";
 import { Crypto } from "@peculiar/webcrypto";