The data they provide is a test set (not a training set) and is from https://tatoeba.org which is in turn under the permissive CC-BY license. You can use that data for anything you like, but you can't use the code in the GitHub repository for commercial purposes - that includes running it to train models.
Academic code often used to be under licenses like this, though it's much less common now.
Awesome articles, thanks! I also found the facebook issue. I am using an ipad, if I tap anywhere in the actual articles, it shows a "share with facebook" dialog (preventing me to follow any of the links in the internal pages). I guess some kind of social sharing plugin is invisibly out of bounds.