Missing Template with edge Rails (2.3)

After freezing edge rails, all my controller examples are failing with
MissingTemplate errors.
e.g., "Missing template attachments/create.erb in view path app/views"

Trying to actually render the views gives me the same error.

I noticed I can fix most of them by using respond_do but I usually
never use it. I almost always only need to respond to one format in
one action so I omit respond_to and let Rails figure out which file to
render.

Will Rails no longer do this in 2.3?

Correction: I meant 'respond_to', not 'respond_do'.

It's trying to render a create view and generally create actions don't
have a view, they just redirect somewhere (probably to the object that
was just created). Make sure in your controller that it's definitely
redirecting or doing *something* other than trying to render that view.

It's not just create, it's seemingly all my actions. I just found this
though:

http://rails.lighthouseapp.com/projects/8994/tickets/1590-xhrs-require-explicit-respond_to