Unable to add additional streams?

Why you can't add additional streams, and what to do about it

If you have been in a call and attempted to share your screen, or add a document camera and have been presented with the message Sorry! Additional streams cannot be added - some participants are using incompatible browsers.  then this article is for you.

Why do I get this error?

As Coviu works in the browser, we have some dependencies on the underlying browser that the call is taking place on. In some cases, different browsers vendors have significant differences in how they've implemented some aspects of their technology stack, which can result in issues with compatibility when attempting to conduct a call with a browser from a different vendor.

For the most part, Coviu has been able to provide an interoperability layer that allows these different browsers to work together to provide the high quality calls that you've come to expect. Unfortunately, there still exist some cases in which we've been unable to resolve the implementation differences between the browser vendors.

The ability to add additional streams is one of these implementation details. Due to implementation of a different media description standard between Mozilla Firefox (on one side) and Google Chrome, Apple Safari 12+, Opera, Brave and Samsung Internet Browser (on the other) means that additional media streams cannot be added when call participants are using Firefox and one of the other browser types.

This means the following situations can happen:

Situations where additional streams can be shared

  • All call participants are using Firefox
  • No call participants are using Firefox

Situations where additional streams cannot be shared

  • At least one call participant is using Firefox, and at least one call participant is not

How do I resolve this?

To solve this error, you will need to identify which user is using Firefox, and see whether there is an option to have participants use a browser that will allow for the addition of additional streams.

What are you doing to resolve this?

This is incompatibility issue is high on our list of critical items to address, however we are having to wait for implementation updates from the browser vendors to support this.

The good news is that Google Chrome has recently shipped an update that will be released in one of the near-future versions that will allow compatibility with Firefox. This will mean that call participants using Google Chrome (once the release is published) will be able to share additional streams with Firefox users, and vice-versa.

We'll keep this help article updated with additional information as it comes to hand.