title: Can I Transpile for ES6-ES5 without npm, VS, Node, etc. and just the JS code itself somehow?
body: <p>I am trying to get Firefox to run a Promise in ES6 but run into the 'let' keyword triggering an error;</p>
  
  <p>SyntaxError: let is a reserved identifier</p>
  
  <p>Changing the script tag to include;
  type="application/javascript;version=1.7"
  did not work, so I am seeking to Transpile the code.</p>
  
  <p>My situation is that there is nothing being used except a text editor. No NPM, not Node or Angular, no Visual Studio, nothing. So when I investigated the Compilers, I saw no option to let me Transpile this code without any of these other tools/editors/etc.</p>
  
  <p>Is there an option where I do not have to learn, use, install, configure, adapt, another tool and just Transpile it outright, or is there some server-specific reason that this cannot be done? What ARE my options?</p>
  
  <p>Thanks in advance! Hoping someone can school me in ES6 and getting it to work with Firefox so it doesn't trigger the errors and use 'let' the way it is intended to be ran.</p>