browser/src/Web/wwwroot/app/settings/views/settingsTwoFactor.html

<div class="modal-header">
    <button type="button" class="close" ng-click="close()" aria-label="Close"><span aria-hidden="true">&times;</span></button>
    <h4 class="modal-title" id="twoFactorModelLabel"><i class="fa fa-key"></i> Two-step Login</h4>
</div>
<form name="authTwoStepForm" ng-submit="authTwoStepForm.$valid && auth(authModel)" api-form="authPromise" ng-if="!twoFactorModel">
    <div class="modal-body">
        <p>Current Status: <span class="label bg-green" ng-show="enabled()">ENABLED</span><span class="label bg-gray" ng-show="!enabled()">DISABLED</span></p>
        <p>Two-step login helps keep your account more secure by requiring a code provided by an app on your mobile device while logging in (in addition to your master password).</p>
        <p ng-show="enabled()">Two-step login is already enabled on your account. To access your two-step settings enter your master password below.</p>
        <p ng-show="!enabled()">To get started with two-step login enter your master password below.</p>
        <div class="callout callout-danger validation-errors" ng-show="authTwoStepForm.$errors">
            <h4>Errors have occured</h4>
            <ul>
                <li ng-repeat="e in authTwoStepForm.$errors">{{e}}</li>
            </ul>
        </div>
        <div class="form-group" show-errors>
            <label for="masterPassword">Master Password</label>
            <input type="password" id="masterPassword" name="MasterPasswordHash" ng-model="authModel.masterPassword" class="form-control" required api-field />
        </div>
    </div>
    <div class="modal-footer">
        <button type="submit" class="btn btn-primary btn-flat" ng-disabled="authTwoStepForm.$loading">
            <i class="fa fa-refresh fa-spin loading-icon" ng-show="authTwoStepForm.$loading"></i>Continue
        </button>
        <button type="button" class="btn btn-default btn-flat" ng-click="close()">Close</button>
    </div>
</form>
<form name="updateTwoStepForm" ng-submit="updateTwoStepForm.$valid && update(updateModel)" api-form="updatePromise" ng-if="twoFactorModel">
    <div class="modal-body">
        <div ng-show="enabled()">
            <p>Two-step login is enabled on your account. Below is the code required by your verification app.</p>
            <p>Need a two-step verification app? Download one of the following:</p>
        </div>
        <div ng-show="!enabled()">
            <p>Setting up two-step verification is easy, just follow these steps:</p>
            <h4>1. Download a two-step verification app</h4>
        </div>
        <ul class="fa-ul">
            <li><i class="fa-li fa fa-apple"></i> iOS devices: <a href="https://itunes.apple.com/en/app/authy/id494168017" target="_blank">Authy for iOS</a></li>
            <li><i class="fa-li fa fa-android"></i> Android devices: <a href="https://play.google.com/store/apps/details?id=com.authy.authy" target="_blank">Authy for Android</a></li>
            <li><i class="fa-li fa fa-windows"></i> Windows devices: <a href="https://www.microsoft.com/en-us/store/apps/authenticator/9wzdncrfj3rj" target="_blank">Microsoft Authenticator </a></li>
        </ul>
        <hr ng-show="enabled()" />
        <h4 ng-show="!enabled()" style="margin-top: 30px;">2. Scan this QR code with your verification app</h4>
        <div class="row">
            <div class="col-md-4 text-center">
                <p><img ng-src="{{twoFactorModel.qr}}" alt="QR" class="img-thumbnail" /></p>
            </div>
            <div class="col-md-8">
                <p><strong>Can't scan the code?</strong> You can add the code to your application manually using the following details:</p>
                <ul class="list-unstyled">
                    <li><strong>Key:</strong> <code>{{twoFactorModel.key}}</code></li>
                    <li><strong>Account:</strong> {{account}}</li>
                    <li><strong>Time based:</strong> Yes</li>
                </ul>
            </div>
        </div>
        <div ng-show="enabled()">
            <hr />
            <h4>Recovery Code</h4>
            <p>
                The recovery code allows you to access your account in the event that you lose your authenticator app.
                bitwarden support won't be able to assist you if you lose access to your account. We recommend you write down or
                print the recovery code below and keep it in a safe place.
            </p>
            <ul class="list-unstyled">
                <li>
                    <strong>Recovery Code:</strong> <code>{{twoFactorModel.recovery}}</code>
                </li>
            </ul>
        </div>
        <div class="callout callout-danger validation-errors" ng-show="updateTwoStepForm.$errors">
            <h4>Errors have occured</h4>
            <ul>
                <li ng-repeat="e in updateTwoStepForm.$errors">{{e}}</li>
            </ul>
        </div>
        <hr ng-show="enabled()" />
        <h4 style="margin-top: 30px;" ng-show="!enabled()">3. Enter the resulting verification code from the app</h4>
        <div class="form-group" show-errors>
            <label for="token" class="sr-only">Verification Code</label>
            <input type="number" id="token" name="Token" placeholder="Verification Code" ng-model="updateModel.token" class="form-control" required api-field />
        </div>
        <p ng-show="!enabled()">NOTE: After enabling two-step login, you will be required to enter the current code generated by your verification app each time you log in.</p>
    </div>
    <div class="modal-footer">
        <button type="submit" class="btn btn-primary btn-flat" ng-disabled="updateTwoStepForm.$loading">
            <i class="fa fa-refresh fa-spin loading-icon" ng-show="updateTwoStepForm.$loading"></i>
            <span ng-show="enabled()">Disable Two-step</span>
            <span ng-show="!enabled()">Enable Two-step</span>
        </button>
        <button type="button" class="btn btn-default btn-flat" ng-click="close()">Close</button>
    </div>
</form>