<ui:composition>
    <c:set var="summaryBtnId" value="${empty id ? 'save': id}"/>

<a4j:commandButton id="${empty id ? 'save': id}" value="Save Changes" action="#{action.toString}" reRender="#{reRender}"
                       onclick="removeSpacesFromInputFields(); if (!checkMandatoryForVisible()){return false}"/>

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<ui:remove>
        The below script is added to invoke the Save Changes button when the user clicks Ctrl + S  
    </ui:remove>

    <script type="text/javascript">
        var isCtrl = false;
        document.onkeyup=function(e){
            var e=window.event || e ;
            var keyunicode=e.charCode || e.keyCode;
            if(keyunicode == 17) isCtrl=false;
        }
        document.onkeydown=function(e){
            var e=window.event || e ;
            var keyunicode=e.charCode || e.keyCode;
            if(keyunicode == 17) isCtrl=true;
            if(keyunicode == 83) {
                if(isCtrl == true){
                    document.getElementById('#{rich:clientId(summaryBtnId)}').click();
                    return false;
                }
            }
        }
    </script>
</ui:composition>