otwarchive-sunsetarchive/app/views/collection_participants/_add_participants_form.html.erb

<%= form_tag add_collection_participants_path(@collection), class: "single simple post", method: :get do %>
  <fieldset>
    <legend>Add new members</legend>
    <p>
      <%= label_tag :participants_to_invite, ts("Add new members"), class: "landmark" %>
      <%= text_field_tag :participants_to_invite, nil, autocomplete_options("pseud") %>
      <span class="submit actions"><%= submit_tag ts("Submit") %></span>
    </p>
  </fieldset>
<% end %>