diff --git a/app/models/spree/line_item_decorator.rb b/app/models/spree/line_item_decorator.rb
index 148e960e..0226f587 100644
--- a/app/models/spree/line_item_decorator.rb
+++ b/app/models/spree/line_item_decorator.rb
@@ -40,7 +40,7 @@ def quantity_by_variant
     private
 
     def update_inventory
-      if (changed? || target_shipment.present?) &&
+      if (saved_changes? || target_shipment.present?) &&
          order.has_checkout_step?("delivery")
         if product.assembly?
           OrderInventoryAssembly.new(self).verify(target_shipment)
diff --git a/spec/support/capybara.rb b/spec/support/capybara.rb
index 960eddd3..0715453f 100644
--- a/spec/support/capybara.rb
+++ b/spec/support/capybara.rb
@@ -2,6 +2,7 @@
 require 'capybara/rails'
 require 'capybara-screenshot/rspec'
 require 'selenium-webdriver'
+require 'webdrivers'
 
 Capybara.register_driver :chrome do |app|
   Capybara::Selenium::Driver.new app,
diff --git a/spree_product_assembly.gemspec b/spree_product_assembly.gemspec
index 3a8e66ec..4522485d 100644
--- a/spree_product_assembly.gemspec
+++ b/spree_product_assembly.gemspec
@@ -28,6 +28,7 @@ Gem::Specification.new do |s|
   s.add_development_dependency 'launchy'
   s.add_development_dependency 'pg', '~> 0.18'
   s.add_development_dependency 'selenium-webdriver'
+  s.add_development_dependency 'webdrivers'
   s.add_development_dependency 'rspec-rails'
   s.add_development_dependency 'sass-rails'
   s.add_development_dependency 'simplecov'