title: why am i getting this routing error? ActionController::RoutingError (No route matches [GET] "/assets/toastr.js.map"):
body: <p>I'm seeing this on localhost and prod:</p>
  
  <p>ActionController::RoutingError (No route matches [GET] "/assets/toastr.js.map"):</p>
  
  <p>I've tried including toastr.js.map in my manifest file: no luck. Also tried renaming the file to toastr.map.js - which immediately started throwing js errors in the console.</p>
  
  <p>Is there a way to either automatically generate map files or ignore them?</p>