HTML标签在PHP AJAX中被剥离

I'm having a hard time understanding why html tags are being stripped from an ajax call but here's very simple code and screenshots to match:

JS

function submitForm()
{
    var data = { description: '<b>Something</b>' };
    $.ajax({
        type: 'POST',
        url: '/edit',
        data: data,
        success: function(data) {
            console.log(data);
        }
    });
}

PHP

public function edit()
{
    var_dump($_POST['description']);exit;
}

HEADERS SCREENSHOT

screenshot-1

RESPONSE SCREENSHOT

screenshot-2

Does anyone know why the response does not show the <b></b> tag that's in the header?

Try $f3->scrub($_POST,'p; br; span; div; b; a');