Sun Aug 16, 2020 4:17 pm
If SSID is hidden, then client device doesn't see it. Period.
How it does work is as following: after client device successfully registers to SSID, it'll keep info about AP (SSID, BSSID, PSK). When it sees AP with same BSSID (which is usually MAC address of AP's wireless interface), it'll know its SSID even though SSID might be hidden now. In this case device might even show SSID but that doesn't mean it's broadcast in wireless beacon.
It could be that some devices only "remember" single BSSID per hidden SSID. In this case device might have problems roaming between APs belonging to same (hidden) SSID and/or re-registering to such network.