On any page of the site, choose the "Log In" link in the corner to load the log in form
Don't enter anything in the field
Press "Log In"
You'll be redirected to the log in page with an error message that includes the sentence "If you still can't log in, please visit Problems When Logging In for help."
The link in that sentence points to admin_posts/1277, which has outdated information.
It should point to to admin_posts/12035.
The path is set in lib/devise_failure_message_options.rb
This will be a relative link, so when testing on staging, you'll have to look at the URL – following the link will give a 404 because a post with that id does not exist on staging.