When I want to open an already existing .ly file in version 4.0.0, I get the following error:

Traceback (most recent call last):
File "/home/falter/frescobaldi-repositories/frescobaldi/frescobaldi/musicview/documents.py", line 70, in documents
self.update()
File "/home/falter/frescobaldi-repositories/frescobaldi/frescobaldi/musicview/documents.py", line 96, in update
doc = pagedview.loadPdf(filename)
^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/falter/frescobaldi-repositories/frescobaldi/frescobaldi/pagedview.py", line 259, in loadPdf
return qpageview.loadPdf(filename, getRenderer("pdf"))
^^^^^^^^^^^^^^^^^^
File "/home/falter/frescobaldi-repositories/frescobaldi/frescobaldi/pagedview.py", line 240, in getRenderer
import qpageview.pdf
File "/home/falter/.local/pipx/venvs/frescobaldi/lib/python3.12/site-packages/qpageview/pdf.py", line 34, in
from PyQt6.QtPdf import QPdfDocument, QPdfDocumentRenderOptions, QPdfLinkModel
ImportError: cannot import name 'QPdfLinkModel' from 'PyQt6.QtPdf' (/usr/lib/python3/dist-packages/PyQt6/QtPdf.abi3.so)

Beschreiben Sie, was Sie getan haben (optional):

Frescobaldi: 4.0.0
Extension API: 0.9.0
Python: 3.12.3
Git branch: master
on commit: f1f9c34
python-ly: 0.9.4
Qt: 6.4.2
PyQt: 6.6.1
qpageview: 1.0.0
OS: Linux-6.8.0-52-generic-x86_64-with-glibc2.39 (Linux Mint 22.1)
Installation kind: distro package or installed from source

Also recompiling the file does not help. There are no LilyPond errors, the PDF is created, but there is no pdf displayed. How can I woo Frescobaldi to display the PDF? Btw, the Manuscript viewer cannot be used as well, of course. Everything works in the flatpak...