# File lib/sup/modes/inbox-mode.rb, line 49
  def multi_archive threads
    UndoManager.register "archiving #{threads.size.pluralize 'thread'}" do
      threads.map do |t|
        t.apply_label :inbox
        add_or_unhide t.first
        Index.save_thread t
      end
      regen_text
    end

    threads.each do |t|
      t.remove_label :inbox
      hide_thread t
    end
    regen_text
    threads.each { |t| Index.save_thread t }
  end