Not connecting to hidden 2.4 wlan after upgrade to 5.3.3

My turris automatically upgraded to 5.3.3 from 3.something. Since then, no device connects to 2.4GHz wlan with hidden SSID. If I switch the wlan to be visible, clients automatically connect. If I switch it back to hidden, they don’t connect again. 5GHz wlan is OK and clients connect regardless it is hidden or not. I did not do any change myself so I consider it to be a bug related to the upgrade. What can I do? Obviously, I want both wlans to be hidden.