Capybara does not play nice Show archive.org snapshot with sites that have some actions protected by SSL, some not. A popular way to implement this in Rails is using the ssl_requirement plugin by DHH, which redirects a requests from HTTP to HTTPS if the requested action requires SSL and vice versa.

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Capybara follows the redirect, but seems to forget the changed protocol for the next request. The only hack-free workaround right now is to use URLs in lieu of paths everywhere (links, form actions).

For a hackful fix, copy the attached file to features/support/ssl_fix.rb.

This issue is fixed Show archive.org snapshot in the Capybara master and should no longer be present in future releases of the gem (I'm writing this on 2011-05-22).