force ssl only if host passed

config/environments/production.rb

@@ -59,7 +59,7 @@ Rails.application.configure do
   # config.action_cable.allowed_request_origins = [ "http://example.com", /http:\/\/example.*/ ]
 
   # Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
-  config.force_ssl = ENV['FORCE_SSL'] == 'true'
+  config.force_ssl = ENV['FORCE_SSL'].present?
 
   # Include generic and useful information about system operation, but avoid logging too much
   # information to avoid inadvertent exposure of personally identifiable information (PII).