zulip/static/templates/stream_member_list_entry.handlebars

<tr data-subscriber-email="{{email}}">
    <td class="subscriber-name">{{name}}</td>
    <td class="subscriber-email">{{email}}</td>
    {{#if displaying_for_admin}}
    <td class="unsubscribe">
        <div class="subscriber_list_remove">
            <form class="form-inline remove-subscriber-form">
                <input type="submit" name="unsubscribe" value="{{t 'Unsubscribe' }}"
                       class="btn btn-danger remove-subscriber-button" />
            </form>
        </div>
    </td>
    {{/if}}
</tr>