Thanks @subs, very interesting to know that is there any solution.
Could you give me more information about modifications needed at wpa-supplicant.conf ?

Thanks for your help.

I CANNOT CONNECT TO MY WIFI NETWORK WHEN SSID IS HIDDEN.
I HAVE TESTED THIS BEHAVIOUR AT RECALBOX 3.3 AND THE LATEST 4 BETA, BUT BOTH OF THEM CANMOT CONNECT TO WIFI NETWORK WHEN WIFI SSID IS HIDDEN.

ONCE YOU SHOW THE WIFI SSID, THE RPI CONNECT WITHOUT PROBLEM, BUT I WOULD LIKE TO HIDE MY SSID WIFI.

HOW CAN WE FIX THIS BUG?