How to make remove display none to this div container in post meta box?

This did the trick, in jQuery:

    //get page title
var edit_title_page=$("html head title").text();

//Confirm if this is right Edit page

if (edit_title_page.indexOf("Edit Form") >= 0) {
    $('#postbox-container-2').removeClass("postbox-container");
    $('#postbox-container-2').css('width','100%');
    $('#postbox-container-2').css('float','left');
    $('#mymetaboxID').show();

}

It will first check for edit page title, if it’s on the right page, remove the post-box container containing the display none, then apply a new css styling.

Finally show the meta box added using add_meta_box, this works for me.

error code: 523