Ok, so with the new change over to the Web Simulator there is a lot of confusion on how to properly debug the application.
The easiest way to get to the tools is to right click and then click on Inspect Element, this will open the Developer Tools to the Elements Tab. From there you have the menu on top that you can explore the various parts in the app. Most notably in the top right hand corner you will see any warnings or errors that come up.
A more detailed look at the Developer Tools can be found on the Google Developers website:
https://developers.google.com/chrome-developer-tools/