PHPstorm PHP syntax not workling witch same class / file names

Hello All,


I have this strange problem.

This is my Zend_View_Helper_ShowPopupMessages.php file:

<?php

class Zend_View_Helper_ShowPopupMessages extends Zend_View_Helper_Abstract
{

     public function showPopupMessages()
    {

     $flashMessenger = Zend_Controller_Action_HelperBroker::getStaticHelper('FlashMessenger');

        if($flashMessenger->hasMessages()) {

            $msg =$flashMessenger->getMessages()[0];

            return "ShowToastMessage('$msg','success')";
        }


    }

} 

as you see the file name and class name are the same and the syntax coloring doesn't work.
When I change the file name to say Zend_View_Helper_ShowPopupMessages1.php coloring works fine.
Also see non php file type icon in the attached picture.

Please help.

Regards
Tom