Yay, it's working! Thx for all the effort.

There is just one thing: I keep getting Opal already loaded. Loading twice can cause troubles, please fix your setup. from /__OPAL_SOURCE_MAPS__/jquery_ujs.js in the js console.

and a minor thing i noticed: for testing this I have added a failing line in app/assets/javascripts/drive/directories.js.rb:5, but the js console shows kernel.rb as the source file. It is ok, since I can expand the error message and click on directories.rb, but I wondered: is it supposed to be like this?

Also I added puts 'foo' to directories.js.rb, but in the js console main.rb is displayed as the source file.

My console output:

@cantonic that's by design, everything is flattened to .rb, this makes it easier to serve stuff from the source maps server. Even if not optimal it makes the system more reliable.

Ah okay, thx for the explanation.