BlockUI - blocking TBODY

HTML

<script src="//cdn.jsdelivr.net/knockout/3.3.0/knockout.js"></script>
<script src="//cdn.jsdelivr.net/jquery.blockui/2.70.0/jquery.blockUI.min.js"></script>
<button>toggle block</button>
<br>
<br>

<table border=1>
    <tbody>
        <tr>
            <td>don't block me</td>
            <td>don't block me</td>
            <td>don't block me</td>
        </tr>
        <tr>
            <td>don't block me</td>
            <td>don't block me</td>
            <td>don't block me</td>
        </tr>
        <tr>
            <td>don't block me</td>
            <td>don't block me</td>
            <td>don't block me</td>
        </tr>
    </tbody>
    <tbody class="blockMe">
        <tr>
            <td>block me</td>
            <td>block me</td>
            <td>block me</td>
        </tr>
        <tr>
            <td>block me</td>
            <td>block me</td>
            <td>block me</td>
        </tr>
        <tr>
            <td>block me</td>
            <td>block me</td>
            <td>block me</td>
        </tr>
    </tbody>
    <tbody>
        <tr>
            <td>don't block me</td>
            <td>don't block me</td>
            <td>don't block me</td>
        </tr>
        <tr>
            <td>don't block me</td>
            <td>don't block me</td>
            <td>don't block me</td>
        </tr>
        <tr>
            <td>don't block me</td>
            <td>don't block me</td>
            <td>don't block me</td>
        </tr>
    </tbody>
</table>

CSS

div {
    border: 1px solid gray;
    padding: .5em;
}

JavaScript

var isBlocked = false;

function toggleBlock(element) {
    debugger;
    
    if(isBlocked){
        $(element).find("td:first").unblock();
        $(element).find("td:not(:first)").unblock();
    }
    else{
        var options = {message: "Blocked!", css: { padding: 0, margin: 0, top: '1px', left: '1px', width: '80%', textAlign: 'left', color: '#000', border: '2px solid #aaa', backgroundColor: '#fff', cursor: 'wait' }};
        
        
        //here's the beef
        $(element).find("td:first").block(options);
        $(element).find("td:not(:first)").block({message: null});
        //end beef
    }
    
    isBlocked = !isBlocked;
}

$("button").click(function(){
    toggleBlock($(".blockMe"));
});