Hello,
The Shortcode Button below the TinyMCE Editor is missing.
How can i get it?

Dear Sir

It is relate to your editor, Please go to the file: plugins\system\ytshortcodes\ytshortcodes.php and find:
$page = str_replace('<div id="editor-xtd-buttons">', '<div id="editor-xtd-buttons">' . $button, $page);
$page = str_replace('<div id="editor-xtd-buttons" class="btn-toolbar pull-left">', '<div id="editor-xtd-buttons" class="btn-toolbar pull-left">' . $button, $page);

=> Edit to:
$version = new JVersion();
if($version->RELEASE < '3.5' ){
$page = str_replace('<div id="editor-xtd-buttons">', '<div id="editor-xtd-buttons">' . $button, $page);
$page = str_replace('<div id="editor-xtd-buttons" class="btn-toolbar pull-left">', '<div id="editor-xtd-buttons" class="btn-toolbar pull-left">' . $button, $page);
}else
{
$app = JFactory::getApplication();
$editor = $app->getCfg('editor');
if($editor == "tinymce")
{
$page = str_replace('<div class="toggle-editor btn-toolbar pull-right clearfix">','<div id="editor-xtd-buttons" class="btn-toolbar pull-left">'. $button.'</div><div class="toggle-editor btn-toolbar pull-right clearfix">', $page);
}else{
$page = str_replace('<div id="editor-xtd-buttons" class="btn-toolbar pull-left">', '<div id="editor-xtd-buttons" class="btn-toolbar pull-left">' . $button, $page);
}
}

thanks