Warning: This guide intended for Rails 5.2, and may be incompletefor Rails 6 setup. This guide will be updated once Rails 6.1 comes out.
This is direction for Migration from c9.io to AWS Cloud9, after you follow the cloud9 migration directions and created a workspace, keeping in mind the Workspace settings Section below.
Be sure you are using the right version of rails. You may need to remove rails and rail-ties and install rails 5.2.