Tests dont pass using let to declare variables instead of var

[atxrenegade]

Using let results in the following error:
Capybara::Poltergeist::JavascriptError:
One or more errors were raised in the Javascript code on the page. If you don't care about
these errors, you can ignore them by setting js_errors: false in your Poltergeist configuration (s
ee documentation for details).

   ReferenceError: Can't find variable: hideWhenClicked

[drakeltheryuujin]

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