JavaScript Console

When using vline.js, critical errors will be displayed in the JavaScript console. Take a look at the Chrome Console instructions or the Firefox Web Console instructions for detailed instructions on how to view and use the console.

JavaScript Exceptions

Exceptions that occur in your JavaScript code, or especially other third-party libraries that you include, can cause the JavaScript in the page to stop executing, which prevents vline.js  from running. To verify that exceptions are not causing a problem you can pause on exceptions in Chrome or Firefox.

Promise Error Handlers

Whenever you use a vline.Promise, you should always make sure to handle the failure case, either by using fail, or by including a failure callback when using then. See the vline.Promise  documentation for more details and examples.

Common Exceptions


This exception occurs when vline.js fails to access to the camera. Verify that you have a camera attached to your computer and that you gave access to the camera when it was requested by the browser. In Chrome, if the page is served over HTTPS and you deny access to the camera, that deny setting will be saved as described in this Chrome support article.

To verify your media permissions are correct, make sure the settings look like this:


If you are still stuck, take a look at our support page. We're always happy to help.