app/views/auth/groups.html.erb
<div class='auth-groups well'>
<% if can? :impersonate, User %>
<div class='panel panel-info'>
<div class='panel-heading'>
<h3 class='panel-title'>Your Current Groups</h3>
</div>
<div class='panel-body'>
<ul class='list-unstyled'>
<% current_user.groups.each do |group| %>
<li>
<%= group %>
</li>
<% end %>
</ul>
</div>
</div>
<div>
<%= form_tag(auth_remember_impersonated_groups_path) do %>
<div class='mb-3'>
<%= label_tag :groups, 'Enter a group or a comma separated list of groups to impersonate' %>
<%= text_field_tag :groups, nil, class: 'form-control', autocomplete: 'off' %>
</div>
<%= submit_tag 'Impersonate', class: 'btn btn-primary btn-lg btn-block' %>
<%= link_to 'Cancel', :back, class: 'btn btn btn-secondary btn-lg btn-block' %>
<% end %>
</div>
<% end %>
</div>