move the listen gem in the Gemfile to the development group

railties/lib/rails/generators/rails/app/templates/Gemfile

@@ -48,11 +48,12 @@ group :development do
   # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
   gem 'spring'
 <% end -%>
+
+  # Loading the listen gem enables an evented file system monitor. Check
+  # https://github.com/guard/listen#listen-adapters if on Windows or *BSD.
+  # gem 'listen', '~> 3.0.3'
 end
 <% end -%>
 
 # Windows does not include zoneinfo files, so bundle the tzinfo-data gem
 gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw, :jruby]
-
-# Uncomment this, to increase the performance
-# gem 'listen', '~> 3.0.3'