I made the change you suggest, now get this:
/usr/local/bundle/gems/webpacker-4.3.0/lib/webpacker/configuration.rb:95:in `rescue in load’: Webpacker configuration file not found /usr/src/app/config/webpacker.yml. Please run rails webpacker:install Error: No such file or directory @ rb_sysopen - /usr/src/app/config/webpacker.yml (RuntimeError)
Can anyone help? Frustrating to pay so much for a book that is incorrect.