If you use a hero, use this option:
config.omniauth :facebook, ENV['FB_APP_ID'], ENV['FB_APP_SECRET'], {:scope => 'email, offline_access', :client_options => {:ssl => {:ca_file => '/usr/lib/ssl/certs/ca-certificates.crt'}}, :display => 'popup' }
kravc Feb 25 2018-12-25T00: 00Z
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