How to detect a JavaScript error?

If you meet one of the following front office features issues when you test one of our modules:

• Nothing happens when you click on a button / a tab
• Buttons don't appear
• Items on your page don't appear 
• A pop-up doesn't appear
• Your conversion tracking tag doesn't work

this may have several causes, including a JavaScript error in the module, theme or another script. The console helps identify the affected file, but does not always establish the root cause. JavaScript errors can be silent on the page: the technical message is then visible in the Console. But, so that we can know what caused the error, we need you to send us a screenshot of the error. Here is the procedure for displaying the error clearly:

One of the features issues listed above is matching, then apply this procedure:

If needed to identify original files, temporarily disable Smart cache for JavaScript under Advanced Parameters > Performance > CCC. You can start by inspecting the console without changing this setting.

- Then go back to the front-office and on the page where the problem occurs, right click and select "Inspect":

The development tool console opens. Click the "Console" tab. Reproduce the display problem. You should see one or several errors in red appear in the console:

Make a screenshot of the errors and send it to us via our contact form, we will help identify its origin and the next diagnostic steps.

Change Smart cache for JavaScript only temporarily for diagnosis, when needed to identify original files, then restore its original setting. You can inspect the console first without changing this setting. If no error appears, also send the reproduction steps; an empty console does not prove that the feature works.

Teaching example triggered on the official Chrome demo. Record the message, source file and line. This example does not identify an error specific to your module.