I'm using MicroOS with the Gnome desktop and SELinux enabled (as per the default settings in the installer).

I've installed protovpn-gui in a toolbox with the --recommends flag. When I run protonvpn from within the toolbox, I get the following error:

Traceback (most recent call last):
  File "/usr/bin/protonvpn", line 33, in <module>
    sys.exit(load_entry_point('protonvpn-gui==1.7.0', 'console_scripts', 'protonvpn')())
  File "/usr/bin/protonvpn", line 25, in importlib_load_entry_point
    return next(matches).load()
  File "/usr/lib64/python3.8/importlib/metadata.py", line 77, in load
    module = import_module(match.group('module'))
  File "/usr/lib64/python3.8/importlib/__init__.py", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1014, in _gcd_import
  File "<frozen importlib._bootstrap>", line 991, in _find_and_load
  File "<frozen importlib._bootstrap>", line 975, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 671, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 843, in exec_module
  File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
  File "/usr/lib/python3.8/site-packages/protonvpn_gui/main.py", line 16, in <module>
    from protonvpn_nm_lib.api import protonvpn
  File "/usr/lib/python3.8/site-packages/protonvpn_nm_lib/api.py", line 6, in <module>
    from .core.report import BugReport
  File "/usr/lib/python3.8/site-packages/protonvpn_nm_lib/core/report/__init__.py", line 1, in <module>
    from .bug import BugReport
  File "/usr/lib/python3.8/site-packages/protonvpn_nm_lib/core/report/bug.py", line 7, in <module>
    from ..subprocess_wrapper import subprocess
  File "/usr/lib/python3.8/site-packages/protonvpn_nm_lib/core/subprocess_wrapper.py", line 123, in <module>
    subprocess = SubprocessWrapper() # noqa
  File "/usr/lib/python3.8/site-packages/protonvpn_nm_lib/core/subprocess_wrapper.py", line 34, in __init__
  File "/usr/lib/python3.8/site-packages/protonvpn_nm_lib/core/subprocess_wrapper.py", line 81, in __ensure_executables_exist
    raise RuntimeError(
RuntimeError: Couldn't find acceptable executables for {'xdg-open'}
I'd appreciate any help with this.

If you are using protonvpn-gui on MicroOS, do you install it as an rpm on the base system, instead of running it from within a toolbox?