Description of problem:
I can reproduce the error again 

Version-Release number of selected component:
lpf-0.2-18.20210903.414f14e.fc33

Additional info:
reporter:       libreport-2.15.2
cgroup:         0::/user.slice/user-1000.slice/user/app.slice/app-\x2fusr\x2fbin\x2fkonsole-110e73d7b0454e788a3bae13ceafc6a7.scope
cmdline:        /usr/bin/python3 /usr/bin/lpf-gui
crash_function: run
exception_type: subprocess.CalledProcessError
executable:     /usr/bin/lpf-gui
interpreter:    python3-3.9.7-1.fc33.x86_64
kernel:         5.14.2-300.fc33.x86_64
runlevel:       N 5
type:           Python3
uid:            1002

Truncated backtrace:
subprocess.py:528:run:subprocess.CalledProcessError: Command '['/usr/share/lpf/scripts/lpf', 'state']' returned non-zero exit status 1.

Traceback (most recent call last):
  File "/usr/bin/lpf-gui", line 14, in <module>
    lpf_gui_base.main()
  File "/usr/share/lpf/scripts/lpf_gui_base.py", line 459, in main
    Handler(builder)
  File "/usr/share/lpf/scripts/lpf_gui_base.py", line 427, in __init__
    statebytes = subprocess.check_output([here('lpf'), 'state'])
  File "/usr/lib64/python3.9/subprocess.py", line 424, in check_output
    return run(*popenargs, stdout=PIPE, timeout=timeout, check=True,
  File "/usr/lib64/python3.9/subprocess.py", line 528, in run
    raise CalledProcessError(retcode, process.args,
subprocess.CalledProcessError: Command '['/usr/share/lpf/scripts/lpf', 'state']' returned non-zero exit status 1.

Local variables in innermost frame:
input: None
capture_output: False
timeout: None
check: True
popenargs: (['/usr/share/lpf/scripts/lpf', 'state'],)
kwargs: {'stdout': -1}
process: <Popen: returncode: 1 args: ['/usr/share/lpf/scripts/lpf', 'state']>
stdout: b''
stderr: None
retcode: 1