I believe I have it now reliably. Was a bit more tricky than I thought. Let me test a bit more and try to remember what I did (we do not have a dedicated advanced-camera thread on TMO? so where would be best place to write down?)
#peterleinchen: advanced-cam as default devel-su cp /usr/bin/harbour-advanced-camera /usr/bin/harbour-advanced-camera-lockscreen cp -ra /usr/share/harbour-advanced-camera /usr/share/harbour-advanced-camera-lockscreen cp /usr/share/applications/harbour-advanced-camera.desktop /usr/share/applications/harbour-advanced-camera-lockscreen.desktop vi /usr/share/applications/harbour-advanced-camera-lockscreen.desktop -->edit as below: Exec=harbour-advanced-camera-lockscreen NoDisplay=true vi /usr/share/applications/jolla-camera-lockscreen.desktop -->edit as below: #Exec=invoker -s --type=silica-media,silica-qt5 /usr/bin/jolla-camera-lockscreen Exec=harbour-advanced-camera-lockscreen systemctl-user restart lipstick