JSFiddle - React, Tailwind, and code Playground

HTML

<input type="checkbox" name="pgManageCS:frmManageCS:pbSettings:pbsDupeMatch:pbsiDupeMatch:chkwebsiteDomain" id="pgManageCS:frmManageCS:pbSettings:pbsDupeMatch:pbsiDupeMatch:chkwebsiteDomain">
<input id="pgManageCS:frmManageCS:pbSettings:pbsDupeMatch:icConvMatchFieldInLeadForAccount" type="text" value="Company" size="20" name="pgManageCS:frmManageCS:pbSettings:pbsDupeMatch:icConvMatchFieldInLeadForAccount" maxlength="80">

JavaScript

$(document).ready(function () {

   $('[id="pgManageCS:frmManageCS:pbSettings:pbsDupeMatch:pbsiDupeMatch:chkwebsiteDomain"]').change(function() {
       if( $(this).is(':checked')) {
         $(this).next().val('Website_Domain__c');
       }
       else{
        $(this).next().val('Company');
       }
    });

});