I installed devise_invitable 1.5.2 with devise 4.1. Gem installed successfully, but when i run server i am getting following error:
alias_method': undefined method
attributes_for' for class `Devise::ParameterSanitizer' (NameError)
I was getting same error with devise 4.0 and devise_invitable 1.5. I fixed this error by installing latest version of devise_invitable 1.6.0 . Now it works with devise 4.0. Hope this will work for you.
I followed this link