Unable to use Qubes Updates on `sys-gui`: [Errno 13] Permission denied

[peakunshift]

Qubes OS release

4.2.0

Brief summary

When using sys-gui there is a permission error that prevents Qubes Updates to open.

I'm reporting this specific issue but it's not the only app with this error. I started a topic on the forum around a more general discussion regarding admin privileges for GuiVMs: https://forum.qubes-os.org/t/grant-full-admin-privileges-to-sys-gui-sys-gui-gpu/

Steps to reproduce

• Install sys-gui and log into it
• Open Qubes Updates

Expected behavior

• Qubes Updates opens as expected

Actual behavior

Permission error reported on the Bug Report UI tool of sys-gui:

backtrace
__init__.py:1213:_open:PermissionError: [Errno 13] Permission denied: '/var/log/qubes/qui.updater.log'

Traceback (most recent call last):
  File "/usr/bin/qubes-update-gui", line 33, in <module>
    sys.exit(load_entry_point('qui==0.1', 'gui_scripts', 'qubes-update-gui')())
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/site-packages/qui/updater/updater.py", line 303, in main
    app = QubesUpdater(qapp, cliargs)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/site-packages/qui/updater/updater.py", line 47, in __init__
    log_handler = logging.FileHandler(
                  ^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib64/python3.11/logging/__init__.py", line 1181, in __init__
    StreamHandler.__init__(self, self._open())
                                 ^^^^^^^^^^^^
  File "/usr/lib64/python3.11/logging/__init__.py", line 1213, in _open
    return open_func(self.baseFilename, self.mode,
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
PermissionError: [Errno 13] Permission denied: '/var/log/qubes/qui.updater.log'