<table class="table table-striped dashboardlisting">
    <thead>
        <tr>
            <th>{{ __('Username') }}</th>
            <th>{{ __('Last seen') }}</th>
            <th>{{ __('Session expires') }}</th>
            <th>{{ __('IP address') }}</th>
            <th>{{ __('Browser / platform') }}</th>
        </tr>
    </thead>

    <tbody>
        {% for session in context.sessions %}
            <tr>
                <td>{{ session.username }}</td>
                <td>
                    <time class="moment" datetime="{{ session.lastseen|date("c") }}" title="{{ session.lastseen }}">{{ session.lastseen }}</time>
                </td>
                <td>
                    <time class="moment" datetime="{{ session.validity|date("c") }}" title="{{ session.validity }}">{{ session.validity }}</time>
                </td>
                <td>
                    {{ session.ip }}
                </td>
                <td>
                    <span class="useragent label info-pop" data-ua="{{ session.useragent }}" data-html="true"
                          data-content="{{ session.useragent }}">{{ session.browser }}</span>
                </td>
            </tr>
        {% endfor %}
    </tbody>
</table>

<table class="table table-striped dashboardlisting">
    <thead>
        <tr>
            <th>{{ __('Username') }}</th>
            <th>{{ __('Last seen') }}</th>
            <th>{{ __('Session expires') }}</th>
            <th>{{ __('IP address') }}</th>
            <th>{{ __('Browser / platform') }}</th>
        </tr>
    </thead>

    <tbody>
        {% for session in context.sessions %}
            <tr>
                <td>{{ session.username }}</td>
                <td>
                    <time class="moment" datetime="{{ session.lastseen|date("c") }}" title="{{ session.lastseen }}">{{ session.lastseen }}</time>
                </td>
                <td>
                    <time class="moment" datetime="{{ session.validity|date("c") }}" title="{{ session.validity }}">{{ session.validity }}</time>
                </td>
                <td>
                    {{ session.ip }}
                </td>
                <td>
                    <span class="useragent label info-pop" data-html="true"
                          data-content="{{ session.useragent }}">{{ session.browser }}</span>
                </td>
            </tr>
        {% endfor %}
    </tbody>
</table>

Remove data-ua, as mentioned by @rarila
Remove data-ua, as mentioned by @rarila