The purpose of this extension is to isolate Facebook. So yes, when you click a link to Facebook, it will open it in a dedicated Facebook container. It would be

The purpose of this extension is to isolate Facebook. So yes, when you click a link to Facebook, it will open it in a dedicated Facebook container. It would be counter intuitive if this is how the standard Containers extension worked, but for this specific extension, you are installing it to isolate Facebook, so I think this is how people would expect it to work. If the extension did not open Facebook links in a dedicated Facebook container, then I think the extension would not be doing its job correctly.