diff --git a/solidus_related_products.gemspec b/solidus_related_products.gemspec
index e65a353..863c3e6 100644
--- a/solidus_related_products.gemspec
+++ b/solidus_related_products.gemspec
@@ -35,6 +35,7 @@ Gem::Specification.new do |spec|
   spec.add_dependency 'deface', '~> 1.0'
 
   spec.add_development_dependency 'solidus_dev_support', '~> 2.3'
+  spec.add_development_dependency 'autoprefixer-rails', '~> 10.2.5'
   spec.add_development_dependency 'rspec-activemodel-mocks'
   spec.add_development_dependency 'shoulda-matchers'
 end