Customize PeopleTools 8.54 signin.html - force userid to uppercase before submitting the form

I am doing the PeopleTools 8.52 to 8.54 upgrade.  I try to apply the same customization of force uppercase of the userid by changeing signin.html userid input as this:

<div class="ps_box-control">

<input type="text" id="userid" name="userid" style="text-transform:uppercase" onkeyup="javascript:this.value=this.value.toUpperCase()" placeholder="%=133%" value="<%=USERID%>" title="<%=133%>">

</div>

User found that it is confusing that ID always appears in uppercase, even their keyboard is NOT in CAP lock.  So I change to uppercase to be a java function call for the Form onsubmit action. But seems like the java function was not executed when the signin.html was invoked.  Yet when I run the same copy of signin.html at my local machine, the function was executed.