You are correct! Sorry, didn't copy/paste line 113. :smile: 

```ruby
def whitelist
  whitelist = Hash[context[:whitelist] || WHITELIST]
  whitelist[:protocols] = Hash[whitelist[:protocols]]
  whitelist[:protocols]['a'] = (whitelist[:protocols]['a'] || {}).merge('href' => anchor_schemes)
  whitelist
end
```

`Marshal.load(Marshal.dump(context[:whitelist] || WHITELIST))` gets us to one line.  Normally, its pretty slow. :frowning:

For fun, I wrote a [super simple benchmark](https://gist.github.com/simeonwillbanks/8428172) to double check.  Across rubies and runs, `Hash#[]` was faster than `Hash#dup`.