zk uses the deprecated api function jquery.bind https://api.jquery.com/bind/

this function is deprecated since jquery 3.0

it can be replaced with jquery.on https://api.jquery.com/on/

same applies to jquery.unbind -> jquery.off

here at a few usages even overriding this function as zbind/zunbind
https://github.com/zkoss/zk/search?q=zbind&unscoped_q=zbind