How do you add a dynamic character count in a text or textarea field

I have a simple text fields with a maximum allowed characters of 120.

I am trying to work out how to display the number of charters available in real-time while the user adds text into the fields.

How do you do this in Wappler without adding an external script, I can figure out how to count the characters but it does not update in real-time.

Similar to the way this works?

https://codepen.io/borisplotkin/pen/RPwXeK