diff --git a/res/css/_components.scss b/res/css/_components.scss
index d8e5247f9d..c8985cbb51 100644
--- a/res/css/_components.scss
+++ b/res/css/_components.scss
@@ -98,6 +98,7 @@
 @import "./views/dialogs/_SpaceSettingsDialog.scss";
 @import "./views/dialogs/_TabbedIntegrationManagerDialog.scss";
 @import "./views/dialogs/_TermsDialog.scss";
+@import "./views/dialogs/_UntrustedDeviceDialog.scss";
 @import "./views/dialogs/_UploadConfirmDialog.scss";
 @import "./views/dialogs/_UserSettingsDialog.scss";
 @import "./views/dialogs/_WidgetCapabilitiesPromptDialog.scss";
diff --git a/res/css/views/dialogs/_UntrustedDeviceDialog.scss b/res/css/views/dialogs/_UntrustedDeviceDialog.scss
new file mode 100644
index 0000000000..0ecd9d4f71
--- /dev/null
+++ b/res/css/views/dialogs/_UntrustedDeviceDialog.scss
@@ -0,0 +1,26 @@
+/*
+Copyright 2021 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+.mx_UntrustedDeviceDialog {
+    .mx_Dialog_title {
+        display: flex;
+        align-items: center;
+
+        .mx_E2EIcon {
+            margin-left: 0;
+        }
+    }
+}
diff --git a/src/components/views/dialogs/UntrustedDeviceDialog.tsx b/src/components/views/dialogs/UntrustedDeviceDialog.tsx
new file mode 100644
index 0000000000..da1492e30d
--- /dev/null
+++ b/src/components/views/dialogs/UntrustedDeviceDialog.tsx
@@ -0,0 +1,73 @@
+/*
+Copyright 2019, 2020, 2021 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import React from "react";
+import { User } from "matrix-js-sdk/src/models/user";
+
+import { _t } from "../../../languageHandler";
+import { MatrixClientPeg } from "../../../MatrixClientPeg";
+import E2EIcon from "../rooms/E2EIcon";
+import AccessibleButton from "../elements/AccessibleButton";
+import BaseDialog from "./BaseDialog";
+import { IDialogProps } from "./IDialogProps";
+import { IDevice } from "../right_panel/UserInfo";
+
+interface IProps extends IDialogProps {
+    user: User;
+    device: IDevice;
+}
+
+const UntrustedDeviceDialog: React.FC<IProps> = ({device, user, onFinished}) => {
+    let askToVerifyText;
+    let newSessionText;
+
+    if (MatrixClientPeg.get().getUserId() === user.userId) {
+        newSessionText = _t("You signed in to a new session without verifying it:");
+        askToVerifyText = _t("Verify your other session using one of the options below.");
+    } else {
+        newSessionText = _t("%(name)s (%(userId)s) signed in to a new session without verifying it:",
+            {name: user.displayName, userId: user.userId});
+        askToVerifyText = _t("Ask this user to verify their session, or manually verify it below.");
+    }
+
+    return <BaseDialog
+        onFinished={onFinished}
+        className="mx_UntrustedDeviceDialog"
+        title={<>
+            <E2EIcon status="warning" size={24} hideTooltip={true} />
+            { _t("Not Trusted")}
+        </>}
+    >
+        <div className="mx_Dialog_content" id='mx_Dialog_content'>
+            <p>{newSessionText}</p>
+            <p>{device.getDisplayName()} ({device.deviceId})</p>
+            <p>{askToVerifyText}</p>
+        </div>
+        <div className='mx_Dialog_buttons'>
+            <AccessibleButton element="button" kind="secondary" onClick={() => onFinished("legacy")}>
+                { _t("Manually Verify by Text") }
+            </AccessibleButton>
+            <AccessibleButton element="button" kind="secondary" onClick={() => onFinished("sas")}>
+                { _t("Interactively verify by Emoji") }
+            </AccessibleButton>
+            <AccessibleButton kind="primary" onClick={() => onFinished(false)}>
+                { _t("Done") }
+            </AccessibleButton>
+        </div>
+    </BaseDialog>;
+};
+
+export default UntrustedDeviceDialog;
diff --git a/src/components/views/right_panel/UserInfo.tsx b/src/components/views/right_panel/UserInfo.tsx
index faf8860cad..d5f67623a2 100644
--- a/src/components/views/right_panel/UserInfo.tsx
+++ b/src/components/views/right_panel/UserInfo.tsx
@@ -67,7 +67,7 @@ import RoomAvatar from "../avatars/RoomAvatar";
 import RoomName from "../elements/RoomName";
 import {mediaFromMxc} from "../../../customisations/Media";
 
-interface IDevice {
+export interface IDevice {
     deviceId: string;
     ambiguous?: boolean;
     getDisplayName(): string;
diff --git a/src/i18n/strings/en_EN.json b/src/i18n/strings/en_EN.json
index b9e52a8356..0b8f3b38e6 100644
--- a/src/i18n/strings/en_EN.json
+++ b/src/i18n/strings/en_EN.json
@@ -578,14 +578,6 @@
     "%(senderName)s updated a ban rule that was matching %(oldGlob)s to matching %(newGlob)s for %(reason)s": "%(senderName)s updated a ban rule that was matching %(oldGlob)s to matching %(newGlob)s for %(reason)s",
     "Light": "Light",
     "Dark": "Dark",
-    "You signed in to a new session without verifying it:": "You signed in to a new session without verifying it:",
-    "Verify your other session using one of the options below.": "Verify your other session using one of the options below.",
-    "%(name)s (%(userId)s) signed in to a new session without verifying it:": "%(name)s (%(userId)s) signed in to a new session without verifying it:",
-    "Ask this user to verify their session, or manually verify it below.": "Ask this user to verify their session, or manually verify it below.",
-    "Not Trusted": "Not Trusted",
-    "Manually Verify by Text": "Manually Verify by Text",
-    "Interactively verify by Emoji": "Interactively verify by Emoji",
-    "Done": "Done",
     "%(displayName)s is typing …": "%(displayName)s is typing …",
     "%(names)s and %(count)s others are typing …|other": "%(names)s and %(count)s others are typing …",
     "%(names)s and %(count)s others are typing …|one": "%(names)s and one other is typing …",
@@ -2067,6 +2059,7 @@
     "Close dialog": "Close dialog",
     "Beta feedback": "Beta feedback",
     "Thank you for your feedback, we really appreciate it.": "Thank you for your feedback, we really appreciate it.",
+    "Done": "Done",
     "%(featureName)s beta feedback": "%(featureName)s beta feedback",
     "Your platform and username will be noted to help us use your feedback as much as we can.": "Your platform and username will be noted to help us use your feedback as much as we can.",
     "To leave the beta, visit your settings.": "To leave the beta, visit your settings.",
@@ -2390,6 +2383,13 @@
     "Summary": "Summary",
     "Document": "Document",
     "Next": "Next",
+    "You signed in to a new session without verifying it:": "You signed in to a new session without verifying it:",
+    "Verify your other session using one of the options below.": "Verify your other session using one of the options below.",
+    "%(name)s (%(userId)s) signed in to a new session without verifying it:": "%(name)s (%(userId)s) signed in to a new session without verifying it:",
+    "Ask this user to verify their session, or manually verify it below.": "Ask this user to verify their session, or manually verify it below.",
+    "Not Trusted": "Not Trusted",
+    "Manually Verify by Text": "Manually Verify by Text",
+    "Interactively verify by Emoji": "Interactively verify by Emoji",
     "Upload files (%(current)s of %(total)s)": "Upload files (%(current)s of %(total)s)",
     "Upload files": "Upload files",
     "Upload all": "Upload all",
diff --git a/src/verification.js b/src/verification.ts
similarity index 62%
rename from src/verification.js
rename to src/verification.ts
index 74e3897d3a..acd9f6d2b2 100644
--- a/src/verification.js
+++ b/src/verification.ts
@@ -1,5 +1,5 @@
 /*
-Copyright 2019, 2020 The Matrix.org Foundation C.I.C.
+Copyright 2019, 2020, 2021 The Matrix.org Foundation C.I.C.
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
@@ -14,16 +14,19 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-import {MatrixClientPeg} from './MatrixClientPeg';
+import { User } from "matrix-js-sdk/src/models/user";
+
+import { MatrixClientPeg } from './MatrixClientPeg';
 import dis from "./dispatcher/dispatcher";
 import Modal from './Modal';
 import * as sdk from './index';
-import { _t } from './languageHandler';
-import {RightPanelPhases} from "./stores/RightPanelStorePhases";
-import {findDMForUser} from './createRoom';
-import {accessSecretStorage} from './SecurityManager';
-import {verificationMethods} from 'matrix-js-sdk/src/crypto';
-import {Action} from './dispatcher/actions';
+import { RightPanelPhases } from "./stores/RightPanelStorePhases";
+import { findDMForUser } from './createRoom';
+import { accessSecretStorage } from './SecurityManager';
+import { verificationMethods } from 'matrix-js-sdk/src/crypto';
+import { Action } from './dispatcher/actions';
+import UntrustedDeviceDialog from "./components/views/dialogs/UntrustedDeviceDialog";
+import {IDevice} from "./components/views/right_panel/UserInfo";
 
 async function enable4SIfNeeded() {
     const cli = MatrixClientPeg.get();
@@ -39,40 +42,7 @@ async function enable4SIfNeeded() {
     return true;
 }
 
-function UntrustedDeviceDialog(props) {
-    const {device, user, onFinished} = props;
-    const BaseDialog = sdk.getComponent("dialogs.BaseDialog");
-    const AccessibleButton = sdk.getComponent("elements.AccessibleButton");
-    let askToVerifyText;
-    let newSessionText;
-
-    if (MatrixClientPeg.get().getUserId() === user.userId) {
-        newSessionText = _t("You signed in to a new session without verifying it:");
-        askToVerifyText = _t("Verify your other session using one of the options below.");
-    } else {
-        newSessionText = _t("%(name)s (%(userId)s) signed in to a new session without verifying it:",
-            {name: user.displayName, userId: user.userId});
-        askToVerifyText = _t("Ask this user to verify their session, or manually verify it below.");
-    }
-
-    return <BaseDialog
-        onFinished={onFinished}
-        headerImage={require("../res/img/e2e/warning.svg")}
-        title={_t("Not Trusted")}>
-        <div className="mx_Dialog_content" id='mx_Dialog_content'>
-            <p>{newSessionText}</p>
-            <p>{device.getDisplayName()} ({device.deviceId})</p>
-            <p>{askToVerifyText}</p>
-        </div>
-        <div className='mx_Dialog_buttons'>
-            <AccessibleButton element="button" kind="secondary" onClick={() => onFinished("legacy")}>{_t("Manually Verify by Text")}</AccessibleButton>
-            <AccessibleButton element="button" kind="secondary" onClick={() => onFinished("sas")}>{_t("Interactively verify by Emoji")}</AccessibleButton>
-            <AccessibleButton kind="primary" onClick={() => onFinished()}>{_t("Done")}</AccessibleButton>
-        </div>
-    </BaseDialog>;
-}
-
-export async function verifyDevice(user, device) {
+export async function verifyDevice(user: User, device: IDevice) {
     const cli = MatrixClientPeg.get();
     if (cli.isGuest()) {
         dis.dispatch({action: 'require_registration'});
@@ -115,7 +85,7 @@ export async function verifyDevice(user, device) {
     });
 }
 
-export async function legacyVerifyUser(user) {
+export async function legacyVerifyUser(user: User) {
     const cli = MatrixClientPeg.get();
     if (cli.isGuest()) {
         dis.dispatch({action: 'require_registration'});
@@ -135,7 +105,7 @@ export async function legacyVerifyUser(user) {
     });
 }
 
-export async function verifyUser(user) {
+export async function verifyUser(user: User) {
     const cli = MatrixClientPeg.get();
     if (cli.isGuest()) {
         dis.dispatch({action: 'require_registration'});
@@ -155,7 +125,7 @@ export async function verifyUser(user) {
     });
 }
 
-export function pendingVerificationRequestForUser(user) {
+export function pendingVerificationRequestForUser(user: User) {
     const cli = MatrixClientPeg.get();
     const dmRoom = findDMForUser(cli, user.userId);
     if (dmRoom) {