No version that supports Spring 3.0

[kroehre]

d61ae74 brought support for spring 3.0, but there isn't a version until 2.1.0 which requires spring 4.0 (da75829)

[gasi]

Ditto. I use this workaround in our Gemfile:

# NOTE: Newest version that doesn’t require Spring 4.x. Unfortunately, it was
# never released, but we can grab it via explicit Git reference:
# https://github.com/rails/spring-watcher-listen/issues/35
gem(
  'spring-watcher-listen',
  git: 'https://github.com/rails/spring-watcher-listen.git',
  ref: 'd61ae74ac8462aef863592eea0e417d3ca31d6af'
)