/usr/lib/ruby/vendor_ruby/ is in ruby-browser 1.0.1-1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/vendor_ruby/browser/
/usr/lib/ruby/vendor_ruby/browser/action_controller.rb
/usr/lib/ruby/vendor_ruby/browser/middleware/
/usr/lib/ruby/vendor_ruby/browser/middleware/context.rb
/usr/lib/ruby/vendor_ruby/browser/middleware/context/
/usr/lib/ruby/vendor_ruby/browser/middleware/context/url_methods.rb
/usr/lib/ruby/vendor_ruby/browser/middleware/context/additions.rb
/usr/lib/ruby/vendor_ruby/browser/rails.rb
/usr/lib/ruby/vendor_ruby/browser/meta/
/usr/lib/ruby/vendor_ruby/browser/meta/id.rb
/usr/lib/ruby/vendor_ruby/browser/meta/generic_browser.rb
/usr/lib/ruby/vendor_ruby/browser/meta/ios.rb
/usr/lib/ruby/vendor_ruby/browser/meta/webkit.rb
/usr/lib/ruby/vendor_ruby/browser/meta/safari.rb
/usr/lib/ruby/vendor_ruby/browser/meta/ie.rb
/usr/lib/ruby/vendor_ruby/browser/meta/base.rb
/usr/lib/ruby/vendor_ruby/browser/meta/platform.rb
/usr/lib/ruby/vendor_ruby/browser/meta/modern.rb
/usr/lib/ruby/vendor_ruby/browser/meta/mobile.rb
/usr/lib/ruby/vendor_ruby/browser/middleware.rb
/usr/lib/ruby/vendor_ruby/browser/methods/
/usr/lib/ruby/vendor_ruby/browser/methods/tv.rb
/usr/lib/ruby/vendor_ruby/browser/methods/ie.rb
/usr/lib/ruby/vendor_ruby/browser/methods/consoles.rb
/usr/lib/ruby/vendor_ruby/browser/methods/devices.rb
/usr/lib/ruby/vendor_ruby/browser/methods/platform.rb
/usr/lib/ruby/vendor_ruby/browser/methods/language.rb
/usr/lib/ruby/vendor_ruby/browser/methods/bots.rb
/usr/lib/ruby/vendor_ruby/browser/methods/mobile.rb
/usr/lib/ruby/vendor_ruby/browser/version.rb
/usr/lib/ruby/vendor_ruby/browser.rb