ExecJS::RuntimeError using await Unexpected token (48:10)

Question

I am getting a error ExecJS::RuntimeError Unexpected token (48:10) when using await.

> 48 |       for await (let worksheet of wrksheets) {

I am using Rails 5.2 and below are the relevant content of my Gemfile. I am trying this on my local machine with development environment.

source 'https://rubygems.org'
git_source(:github) { |repo| "https://github.com/#{repo}.git" }
gem 'rails', '~> 5.2'
gem 'puma', '~> 3.11'
gem 'sass-rails', '~> 5.0'
# Use Uglifier as compressor for JavaScript assets
gem 'uglifier', '>= 1.3.0'
# See https://github.com/rails/execjs#readme for more supported runtimes
gem 'coffee-rails', '~> 4.2'
gem 'turbolinks', '~> 5'
gem 'jbuilder', '~> 2.5'
gem 'bootsnap', '>= 1.1.0', require: false
group :development, :test do
  # Call 'byebug' anywhere in the code to stop execution and get a debugger console
  gem 'byebug', platforms: [:mri, :mingw, :x64_mingw]
end
group :development do
  gem 'xray-rails'
end
group :production do
  gem 'sprockets-rails'
  gem 'sprockets'
  gem 'babel-transpiler'
  gem 'passenger'
end
gem 'foundation-rails', '= 6.4.3.0'
gem 'autoprefixer-rails'
gem 'bootstrap-multiselect-rails'
gem 'nouislider-rails'

Any help on how i can fix this would be really great. Thanks