Normally, any changes I make to .js.coffee files in my Rails 3.2.0 app in development mode take effect when I refresh the page. All of a sudden, this is not happening. If I do rake assets:precompile, then the changes are shown, but then if I do rake assets:clean they go back to not being shown. What is causing this?

Edit: Restarting the server makes the changes show. Why isn't this happening automatically as before?

Edit: Here is my development.rb

Myapp::Application.configure do
  # Settings specified here will take precedence over those in config/application.rb

  # In the development environment your application's code is reloaded on
  # every request. This slows down response time but is perfect for development
  # since you don't have to restart the web server when you make code changes.
  config.cache_classes = false

  # Log error messages when you accidentally call methods on nil.
  config.whiny_nils = true

  # Show full error reports and disable caching
  config.consider_all_requests_local       = true
  config.action_controller.perform_caching = false

  # Don't care if the mailer can't send
  config.action_mailer.raise_delivery_errors = false

  # Print deprecation notices to the Rails logger
  config.active_support.deprecation = :log

  # Only use best-standards-support built into browsers
  config.action_dispatch.best_standards_support = :builtin

  # Raise exception on mass assignment protection for Active Record models
  config.active_record.mass_assignment_sanitizer = :strict

  # Log the query plan for queries taking more than this (works
  # with SQLite, MySQL, and PostgreSQL)
  config.active_record.auto_explain_threshold_in_seconds = 0.5

  # Do not compress assets
  config.assets.compress = false

  # Expands the lines which load the assets
  config.assets.debug = true
  config.action_mailer.default_url_options = { :host => 'localhost:3000' }

  config.log_level = :warn


end