Crash when clicking on [Decode from Webcam]

Manjaro QtQR version 2.1
HP 850 G4 built in Webcam 'SunplusIT INC. HD Webcam'

when clicking on the Buttom [Decode from Webcam] -> [<select Webcam>] QTQR crashes with:
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Warning: Ignoring XDG_SESSION_TYPE=wayland on Gnome. Use QT_QPA_PLATFORM=wayland to run on Wayland anyway.
QPixmap::scaled: Pixmap is a null pixmap
QPixmap::scaled: Pixmap is a null pixmap
Traceback (most recent call last):
  File "/usr/bin/qtqr", line 899, in decodeWebcam
    qr.decode_webcam(device=device)
  File "/usr/lib/python3.10/site-packages/qrtools.py", line 262, in decode_webcam
    proc.init(device)
zbar.UnsupportedError: <zbar.Processor object at 0x7f8ea35bce40>
Abgebrochen (Speicherabzug geschrieben)
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Sometimes it helps to wait about 1-3 minutes!! before I select the webcam.
(Webcam is working fine with all other programs)