Don't put in self-closing tags on anything.

lib/html5.rb

@@ -16,32 +16,20 @@ def javascript_src_tag_with_empty_type(source, options)
   def stylesheet_tag(source, options)
     tag("link", { "rel" => "stylesheet", "media" => "screen", "href" => html_escape(path_to_stylesheet(source)) }.merge(options), ::SKIP_SELF_CLOSE_TAGS, false)
   end
-
-  def image_tag(source, options = {})
-    options.symbolize_keys!
-
-    options[:src] = path_to_image(source)
-    options[:alt] ||= File.basename(options[:src], '.*').split('.').first.to_s.capitalize
 
-    if size = options.delete(:size)
-      options[:width], options[:height] = size.split("x") if size =~ %r{^\d+x\d+$}
-    end
+end
 
-    if mouseover = options.delete(:mouseover)
-      options[:onmouseover] = "this.src='#{image_path(mouseover)}'"
-      options[:onmouseout]  = "this.src='#{image_path(options[:src])}'"
-    end
-
-    tag("img", options, ::SKIP_SELF_CLOSE_TAGS)
-  end
+module ActionView::Helpers::TagHelper
+  # When served as text/html, tags do not need to be self-closed.
+  # http://www.whatwg.org/specs/web-apps/current-work/#void-elements
+  VOID_ELEMENTS = %w(base command link meta hr br img embed param area col input source)
+  
+  def tag_with_skip_self_closing(name, options = nil, open = false, escape = true)
+    open = true if VOID_ELEMENTS.include?(name.to_s) && ::SKIP_SELF_CLOSE_TAGS
 
-  def auto_discovery_link_tag(type = :rss, url_options = {}, tag_options = {})
-    tag(
-      "link",
-      {"rel"   => tag_options[:rel] || "alternate",
-      "type"  => tag_options[:type] || Mime::Type.lookup_by_extension(type.to_s).to_s,
-      "title" => tag_options[:title] || type.to_s.upcase,
-      "href"  => url_options.is_a?(Hash) ? url_for(url_options.merge(:only_path => false)) : url_options}, ::SKIP_SELF_CLOSE_TAGS
-    )
+    tag_without_skip_self_closing(name, options, open, escape)
   end
-end
+  alias_method_chain :tag, :skip_self_closing
+end
+
+