# File lib/selenium/webdriver/common/profile_helper.rb, line 48
        def from_json(json)
          data = WebDriver.json_load(json).fetch('zip')

          # can't use Tempfile here since it doesn't support File::BINARY mode on 1.8
          # can't use Dir.mktmpdir(&blk) because of http://jira.codehaus.org/browse/JRUBY-4082
          tmp_dir = Dir.mktmpdir
          begin
            zip_path = File.join(tmp_dir, "webdriver-profile-duplicate-#{json.hash}.zip")
            File.open(zip_path, "wb") { |zip_file| zip_file << Base64.decode64(data) }

            new Zipper.unzip(zip_path)
          ensure
            FileUtils.rm_rf tmp_dir
          end
        end