Tinymce html5 placeholder by reading attribute from textarea

Question

For standard textareas I use this plugin to create a placeholder. How can I extend tinymce so that this works in this way also.

E.g the default value is read from the

Answer 1

The answers above were not working for me, but here's my (for me) working code based on the answers above and using onchange_callback. Hope it helps someone!

onchange_callback : function(ed){
            var tinymce_placeholder = $('#' + ed.id).attr("placeholder");     
            setTimeout(function () {
                var content = ed.getContent().replace(/
|<\/p>/g, '');
                if (content == '') {
                    ed.setContent(tinymce_placeholder);
                }
            }, 200);
        },
        setup: function (ed) {
            // Set placeholder
            var tinymce_placeholder = $('#' + ed.id);
            if (tinymce_placeholder.length) {
                ed.onInit.add(function (ed) {
                    var cont = ed.getContent();
                    if (cont.length == 0) {
                        ed.setContent(tinymce_placeholder.attr("placeholder"));
                    }
                });
                ed.onMouseDown.add(function (ed, e) {
                    var content = ed.getContent().replace(/
|<\/p>/g, '');
                    if (content == tinymce_placeholder.attr("placeholder")) {
                        ed.setContent('');
                    }
                });
            }
        }