static/admin/TinyMCETextArea.js
function (txt) {
        var me = this;

        var wwg_mode = false;

        var ed = tinymce.get(me.getInputId());

        if (me.wysiwygIntialized) {
            if (ed && !ed.isHidden()) {
                wwg_mode = true;
            }
        }

        var ctrl = document.getElementById(me.getInputId());

        if (wwg_mode) {
            ed.focus();
            ed.execCommand('mceInsertContent', 0, txt);
        }
        else if (ctrl) {
            ctrl.focus();

            var start = ctrl.selectionStart + txt.length;

            ctrl.value = ctrl.value.slice(0, ctrl.selectionStart) + txt + ctrl.value.slice(ctrl.selectionEnd);

            ctrl.setSelectionRange(start, start);
        }
    }
function (txt) {
        var me = this;

        var wwg_mode = false;

        var ed = tinymce.get(me.getInputId());

        if (me.wysiwygIntialized) {
            if (ed && !ed.isHidden()) {
                wwg_mode = true;
            }
        }

        var ctrl = document.getElementById(me.getInputId());

        if (wwg_mode) {
            ed.focus();
            ed.execCommand('mceInsertContent', 0, txt);
        }
        else if (ctrl) {
            ctrl.focus();

            var start = ctrl.selectionStart + txt.length;

            ctrl.value = ctrl.value.slice(0, ctrl.selectionStart) + txt + ctrl.value.slice(ctrl.selectionEnd);

            ctrl.setSelectionRange(start, start);
        }
    }
restoreCurrentSelection -----------------------------------------------------------------