They used Livecycle (XFA) forms. It's not part of the latest PDF standard.
https://en.wikipedia.org/wiki/XFA
Here is a plain Acroform version :-)
https://send.firefox.com/download/3d2da3ccd62d4ce9/#CJRCa5XO...
https://en.wikipedia.org/wiki/XFA
Here is a plain Acroform version :-)
https://send.firefox.com/download/3d2da3ccd62d4ce9/#CJRCa5XO...
If you asked Adobe, they would say this is not possible. :-)
If you see a way to, make them pay for it; there is money to be made.