UserAgent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Ubuntu Chromium/67.0.3396.99 Chrome/67.0.3396.99 Safari/537.36

Steps to reproduce the problem:
1. Have a project folder containing those files: "static/coffee/lazyload.coffee" (containing a simple "Hello World" console.log), "static/coffee/lazyload.js", "static/coffee/lazyload.js.map"
2. Use a web server like pythons Flask in the project directory to serve these static files.
3. Reference the compiled coffeescript file "lazyload.js" in HTML
4. Open the Chromium DevTools to see the "Hello World" output

What is the expected behavior?
In the JavaScript Console, there will be the "Hello World" message and a link to the source at the right side ("lazyload.coffee:1"), which links to the mapped source file.

What went wrong?
Actually, the source is ("lazyload.js:2"), which is the transpiled file. The source map is not working, although, when I reveal the lazyload.js source in the DevTools, there is a small banner saying "(i) Source Map detected. Associated files should be added to the file tree. You can debug these resolved source files as regular JavaScript files. Associated files are available via file tree or Ctrl+P".

Did this work before? N/A 

Chrome version: 67.0.3396.99  Channel: n/a
OS Version: 
Flash Version: 

I already read through some threads like this: https://github.com/nodejs/node/issues/8369. There are also (closed) chromium bugs referenced in this github conversation. I would like to point out, that I am not using any framework like Node or Electron. All I use, is a simple Python Flask server.

Since the same application is completely working as expected on Firefox, this seems to be clearly a bug related to Chromium. This is the transpiled file:

(function() {
  console.log("Hello World!");

}).call(this);

//# sourceMappingURL=lazyload.js.map

I am using Ubuntu 17.10 with the latest updates.