The problem fixed by disable check encoding via rules in security_mod .. the question is why this problem not happened when I use search page of some modules such as xhelp ?
Fatal error: Call to undefined method SmartsectionForm_EditCategory::XoopsThemeForm() in G:\wamp\www\xoops2\htdocs\modules\smartsection\class\form-editcategory.php on line 22
In 2.3 and 3.0, we are building a mechanism to allow third-party framework integration.