Deform 2.0: Adding HTML5 placeholder

I am trying to add HTML5 placeholder attribute to Deform 2.0 TextInputWidget. However I am not sure if this should be supported or how this should be supported as documentation is not very clear about this - there seems to be some mask_placeholder feature which doesn't be what I want.

How to add HTML5 placeholder to Deform text input (2.0+)?

EDIT: As of Deform 2.0.7, HTML5 attributes are supported.

https://docs.pylonsproject.org/projects/deform/en/latest/changes.html

Ok - the trick is to have a custom template - Deform templates did not yet have support for placeholder:

<!--! This adds placeholder attribute support for TextInput.

 -->

<span tal:define="name name|field.name;
                  css_class css_class|field.widget.css_class;
                  oid oid|field.oid;
                  mask mask|field.widget.mask;
                  mask_placeholder mask_placeholder|field.widget.mask_placeholder;
                  style style|field.widget.style;
                  placeholder field.widget.placeholder|nothing;
                  type field.widget.type|'text';
"
      tal:omit-tag="">
    <input type="${type}" name="${name}" value="${cstruct}"
           tal:attributes="class string: form-control ${css_class};
                           style style;
                           placeholder placeholder;"
           id="${oid}"/>
    <script tal:condition="mask" type="text/javascript">
      deform.addCallback(
         '${oid}',
         function (oid) {
            $("#" + oid).mask("${mask}",
                 {placeholder:"${mask_placeholder}"});
         });
    </script>
</span>

And then you can define your widget as:

class InviteFriends(CSRFSchema):

    email = c.SchemaNode(
        c.String(),
        missing=None,
        validator=c.Email(),
        widget=w.TextInputWidget(template="textinput_placeholder", type="email", placeholder="Friend's email"),
    )

    phone_number = c.SchemaNode(
        c.String(),
        missing=None,
        validator=c.Length(min=7),
        widget=w.TextInputWidget(template="textinput_placeholder", type="tel", placeholder="Friend's phone number"),
    )