thx, this worked!
To summerize the workaround:
create a "/storage/.config/system.d/hiddenSSID.service" with following content:
Code
[Unit]
Description=Hidden SSID Connect Service
After=network-online.target connman.service iwd.service
Wants=network-online.target connman.service iwd.service
Before=kodi.target
[Service]
Type=oneshot
RemainAfterExit=yes
ExecStart=/usr/bin/iwctl --passphrase <PWD> station wlan0 connect-hidden <SSID>
ExecStop=/usr/bin/iwctl station wlan0 disconnect
[Install]
WantedBy=multi-user.target
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enable the service in ssh with "systemctl enable hiddenSSID.service".
That was it, the next reboot Raspi should connect to your hidden network.
O