fixes #1242

app/helpers/application_helper.rb

@@ -1,4 +1,8 @@
 module ApplicationHelper
+  def wordbreakify(string)
+    raw(string.gsub(/(.{10})/, "\\1<wbr>"))
+  end
+
   def nav_link_to(text, url, options = nil)
     if nav_link_match(params[:controller], url)
       klass = "current"

app/helpers/post_versions_helper.rb

@@ -4,14 +4,14 @@ module PostVersionsHelper
     html = []
     diff[:added_tags].each do |tag|
       prefix = diff[:obsolete_added_tags].include?(tag) ? '+<ins class="obsolete">' : '<ins>+'
-      html << prefix + link_to(tag, posts_path(:tags => tag)) + '</ins>'
+      html << prefix + link_to(wordbreakify(tag), posts_path(:tags => tag)) + '</ins>'
     end
     diff[:removed_tags].each do |tag|
       prefix = diff[:obsolete_removed_tags].include?(tag) ? '-<del class="obsolete">' : '<del>-'
-      html << prefix + link_to(tag, posts_path(:tags => tag)) + '</del>'
+      html << prefix + link_to(wordbreakify(tag), posts_path(:tags => tag)) + '</del>'
     end
     diff[:unchanged_tags].each do |tag|
-      html << '<span>' + link_to(tag, posts_path(:tags => tag)) + '</span>'
+      html << '<span>' + link_to(wordbreakify(tag), posts_path(:tags => tag)) + '</span>'
     end
     return html.join(" ").html_safe
   end

app/helpers/posts_helper.rb

@@ -17,10 +17,6 @@ module PostsHelper
     end
   end
 
-  def wordbreakify(string)
-    string.gsub(/(.{15})/, "\\1<wbr>")
-  end
-
   def post_source_tag(post)
     if post.source =~ %r!http://img\d+\.pixiv\.net/img/([^\/]+)/!
       text = "pixiv/<wbr>#{wordbreakify($1)}"