Rails Capybara following render after form submit

In my rails controller i have:

def update
  render @bill if @bill.update(bill_params)
end

On the form i have a remote true, so the render gets loaded on the page using ajax.

But in my capybara tests i have:

fill_in('bill_period', with: @bill.period)
fill_in('bill_groupname', with: @bill.groupname)
click_button 'update bill'
save_and_open_page

The page now opens in the render instead of the page it should be rendering on. It doesnt do this in the application itself only via capybara. How to i prevent capybara from following the render?