<form method='GET' action='<%= url %>' class='search_form'>
  <%= text_field :search, nil, :id => 'search', :type => 'search', :name => 'search', :value => params[:search], :title => t('search_input_notice', :scope => 'refinery.admin.search') %>
  <%= hidden_field :wymeditor, nil, :name => 'wymeditor', :id => nil, :value => true  if params[:wymeditor].presence %>
  <%= hidden_field :dialog, nil, :name => 'dialog', :id => nil, :value => true if from_dialog? %>
  <%= hidden_field :callback, nil, :name => 'callback', :id => nil, :value => @callback if @callback.presence %>
  <%= submit_tag t('button_text', :scope => 'refinery.admin.search'), :name => nil %>
</form>

<form method='GET' action='<%= url %>' class='search_form'>
  <%= text_field :search, nil, :id => 'search', :type => 'text', :name => 'search', :value => params[:search], :title => t('search_input_notice', :scope => 'refinery.admin.search') %>
  <%= hidden_field :wymeditor, nil, :name => 'wymeditor', :id => nil, :value => true  if params[:wymeditor].presence %>
  <%= hidden_field :dialog, nil, :name => 'dialog', :id => nil, :value => true if from_dialog? %>
  <%= hidden_field :callback, nil, :name => 'callback', :id => nil, :value => @callback if @callback.presence %>
  <%= submit_tag t('button_text', :scope => 'refinery.admin.search'), :name => nil %>
</form>

Change the search input for a text input (unstylable in Safari)
Change the search input for a text input (unstylable in Safari)