Yorisoi Remnant Error

<%= form_for @sample, url: create_path, method: :post, builder: Yorisoi::Builder do |f| %> <%= hidden_field :remnant, value: true %>
<%= f.text_field :text, class: [:p100], no_errors: true %>
<%= f.password_field :password, class: [:p100], no_errors: true %>
<%= f.text_area :textarea, class: [:p100], no_errors: true %>
<%= f.select :select, Const::SELECT, {prompt: :select}, {class: [:p100]} %>
<%= f.radio_buttons :radio, {class: [:bigger]}, Const::RADIO.zip(Const::RADIO) %>
<%= f.check_boxes :checkbox, {class: [:bigger]}, Const::CHECKBOX.zip(Const::CHECKBOX) %>
<% end %>
<% self.output_buffer.gsub_not_safety!('', 'a') %> a