-# Note: keeping this out of the "group :assets" section "may" allow us
-# to use Coffescript for UJS responses. It also prevents a
-# warning/problem when running tests: "WARN: tilt autoloading
-# 'coffee_script' in a non thread-safe way; explicit require
-# 'coffee_script' suggested."
-gem 'coffee-rails'
+# Pin sprockets to < 4.0 to avoid issues when upgrading rails to 5.2
+# See: https://github.com/rails/sprockets-rails/issues/443
+gem 'sprockets', '~> 3.0'