Fix for pre EE 2.6

proform_view.php

<?php

class PF_View extends View {
    public function __construct(View $view)
    {
        if(!isset($this->EE)) $this->EE = &get_instance(); // <-- Add this line
        $this->set_cp_theme($view->_theme);
    }
    
    public function head_title($title)
    {
        return parent::head_title(strip_tags($title));
    }
}