1 files changed, 3 insertions, 9 deletions
diff --git a/guides/source/rails_on_rack.md b/guides/source/rails_on_rack.md
index 1fac6d9883..d8477d89e3 100644
--- a/guides/source/rails_on_rack.md
+++ b/guides/source/rails_on_rack.md
@@ -37,11 +37,11 @@ Rails on Rack
 Here's how `rails server` creates an instance of `Rack::Server`
 
 ```ruby
-Rails::Server.new.tap { |server|
+Rails::Server.new.tap do |server|
   require APP_PATH
   Dir.chdir(Rails.application.root)
   server.start
-}
+end
 ```
 
 The `Rails::Server` inherits from `Rack::Server` and calls the `Rack::Server#start` method this way:
@@ -137,7 +137,6 @@ use ActionDispatch::ParamsParser
 use Rack::Head
 use Rack::ConditionalGet
 use Rack::ETag
-use ActionDispatch::BestStandardsSupport
 run MyApp::Application.routes
 ```
 
@@ -215,7 +214,6 @@ And to remove browser related middleware,
 
 ```ruby
 # config/application.rb
-config.middleware.delete "ActionDispatch::BestStandardsSupport"
 config.middleware.delete "Rack::MethodOverride"
 ```
 
@@ -229,7 +227,7 @@ Much of Action Controller's functionality is implemented as Middlewares. The fol
 
  **`Rack::Lock`**
 
-* Sets `env["rack.multithread"]` flag to `true` and wraps the application within a Mutex.
+* Sets `env["rack.multithread"]` flag to `false` and wraps the application within a Mutex.
 
  **`ActiveSupport::Cache::Strategy::LocalCache::Middleware`**
 
@@ -307,10 +305,6 @@ Much of Action Controller's functionality is implemented as Middlewares. The fol
 
 * Adds ETag header on all String bodies. ETags are used to validate cache.
 
- **`ActionDispatch::BestStandardsSupport`**
-
-* Enables “best standards support” so that IE8 renders some elements correctly.
-
 TIP: It's possible to use any of the above middlewares in your custom Rack stack.
 
 ### Using Rack Builder