Rails 5 Migration File Change

[SaimonL]

When I run migration I get this error:

StandardError: An error has occurred, this and all later migrations canceled:

Directly inheriting from ActiveRecord::Migration is not supported. Please specify the Rails release the migration was written for:

The fix is to edit the file: db/migrate/20..19_create_active_configuration_settings.rb

Then change the first line to this (add "[4.2]"):

class CreateActiveConfigurationSettings < ActiveRecord::Migration[4.2]

And now the migration works fine.