TypeError on oninput

[odysseyalive]

In init_v3.php, I'm not sure what the purpose of the oninput call is for? Leaving it causes a TypeError. Validation works without it.

[xtremevision]

I am getting the same error:

(index):548 Uncaught (in promise) TypeError: document.getElementById(...).oninput is not a function
at (index):548:53