Bootstrap-treeview with jquery Ajax Get not showing response

Working with the bootstrap-treeview package in Laravel 5.1:

function getTree() {
    ...
    $.ajax({
            type: 'GET',
            url: loadUrl,
            dataType: "json",
        })
        .done(function (response) {
            return response;
        })
        .fail(function (response) {
            console.log(response);
        });
}
$('#tree').treeview({data: getTree()});

This code is working, it gives me a proper JSON response, so routes etc are correct and working.

When I take the raw response out of firebug and add it as a manual response to getTree (return [the raw json returned by getTree];) bootstrap-treeview shows exactly what's expected.

When I compare both JSON strings (the above method and raw pasted in getTree) in the html source of the page they are EXACTLY the same.

I am pulling my hair out for a day now. What can be the issue here?

via Chebli Mohamed