I have created dynamic link manually and i set some additional parameters on the link, like this: https://XXXXX.goo.gl/?link=https%3A%2F%2Fairbanq.send.com%2Fsendmoney&a
The official answer is that you need to escape/encode a URL string so that it can be safely placed inside a URL query.
I wish Firebase dynamic links would just say that about the link.