@Mimiix thx but apt-get install does that already but i did try again :
pi@phoscon:~ $ sudo apt-get install -y libqt5qml5
Reading package lists... Done
Building dependency tree
Reading state information... Done
libqt5qml5 is already the newest version (5.7.1-2+rpi1).
libqt5qml5 set to manually installed.
0 upgraded, 0 newly installed, 0 to remove and 255 not upgraded.
Jan 14 13:02:57 phoscon systemd[1]: Started deCONZ: ZigBee gateway -- GUI/REST API.
Jan 14 13:02:58 phoscon deCONZ[3115]: libEGL warning: DRI2: failed to authenticate
Jan 14 13:03:01 phoscon systemd[1]: deconz-gui.service: Main process exited, code=exited, status=127/n/a
Jan 14 13:03:04 phoscon systemd[1]: deconz-gui.service: Unit entered failed state.
Jan 14 13:03:04 phoscon systemd[1]: deconz-gui.service: Failed with result 'exit-code'.
UPDATE: I take it back, i thought i did the buster upgrade but didn’t…doing it now. I’ll let you know if this works.