btcpayserver/BTCPayServer/Views/Manage/EnableAuthenticator.cshtml

@model EnableAuthenticatorViewModel
@{
    ViewData["Title"] = "Enable authenticator";
    ViewData.AddActivePage(ManageNavPages.TwoFactorAuthentication);
}

<h4>@ViewData["Title"]</h4>
<div>
    <p>To use an authenticator app go through the following steps:</p>
    <ol class="list">
        <li>
            <p>
                Download a two-factor authenticator app like Microsoft Authenticator for
                <a href="https://go.microsoft.com/fwlink/?Linkid=825071">Windows Phone</a>,
                <a href="https://go.microsoft.com/fwlink/?Linkid=825072">Android</a> and
                <a href="https://go.microsoft.com/fwlink/?Linkid=825073">iOS</a> or
                Google Authenticator for
                <a href="https://play.google.com/store/apps/details?id=com.google.android.apps.authenticator2&amp;hl=en">Android</a> and
                <a href="https://itunes.apple.com/us/app/google-authenticator/id388497605?mt=8">iOS</a>.
            </p>
        </li>
        <li>
            <p>Scan the QR Code or enter this key <kbd>@Model.SharedKey</kbd> into your two factor authenticator app. Spaces and casing do not matter.</p>
            <div id="qrCode"></div>
            <div id="qrCodeData" data-url="@Html.Raw(Model.AuthenticatorUri)"></div>
        </li>
        <li>
            <p>
                Once you have scanned the QR code or input the key above, your two factor authentication app will provide you
                with a unique code. Enter the code in the confirmation box below.
            </p>
            <div class="row">
                <div class="col-md-6">
                    <form method="post">
                        <div class="form-group">
                            <label asp-for="Code" class="control-label">Verification Code</label>
                            <input asp-for="Code" class="form-control" autocomplete="off" />
                            <span asp-validation-for="Code" class="text-danger"></span>
                        </div>
                        <button type="submit" class="btn btn-default">Verify</button>
                        <div asp-validation-summary="ModelOnly" class="text-danger"></div>
                    </form>
                </div>
            </div>
        </li>
    </ol>
</div>

@section Scripts {
    @await Html.PartialAsync("_ValidationScriptsPartial")
    <script type="text/javascript" src="~/js/qrcode.min.js"></script>
    <script type="text/javascript">
        new QRCode(document.getElementById("qrCode"),
            {
                text: "@Html.Raw(Model.AuthenticatorUri)",
                width: 150,
                height: 150
            });
    </script>
}