I close popup window, then I press CTRL+Z in Opera browser, popup open again, but without parameters:
popup.php?sid=c722493b4f4c4126

ERROR: Zabbix has received an incorrect request.
Undefined variable: min_user_type [ in C:\xampp\htdocs\ZBX-2579-trunk\frontends\php\popup.php:150]

I post this issue because in other popups (popup_httpstep.php, popup_media.php, popup_period.php...) don't have same problem.

Popup was in graph->select item