Extensions Manager/ Clipart extension not working in AppImage and Windows builds

Summary:

I tested the Clipart extension in the 1.2b and it does not work both in the AppImage and Windows build.

Steps to reproduce:

On Linux/AppImage build:

Open Extensions -> Manage Extensions produces Error 1

Open Extensions -> Import -> Internet Resource /usr/bin/python3: can't find '__main__' module in '/home/duerr/Downloads/.'

On Windows 11: Extension Manager is working, I was able to uninstall and reinstall the extension. But Extensions -> Import -> Internet Resource produces: ImportError: cannot import name 'inkscape_env' from 'inkex'

What happened?

Error 1

Traceback (most recent call last):
  File "/tmp/.mount_Inksca347kZJ/usr/share/inkscape/extensions/inkman/inkman/manage_extensions.py", line 29, in <module>
    from inkex import gui
  File "/tmp/.mount_Inksca347kZJ/usr/share/inkscape/extensions/inkex/__init__.py", line 11, in <module>
    from .extensions import *
  File "/tmp/.mount_Inksca347kZJ/usr/share/inkscape/extensions/inkex/extensions.py", line 34, in <module>
    from .elements import (
  File "/tmp/.mount_Inksca347kZJ/usr/share/inkscape/extensions/inkex/elements/__init__.py", line 10, in <module>
    from ._base import ShapeElement, BaseElement
  File "/tmp/.mount_Inksca347kZJ/usr/share/inkscape/extensions/inkex/elements/_base.py", line 38, in <module>
    from ..styles import Style, Classes
  File "/tmp/.mount_Inksca347kZJ/usr/share/inkscape/extensions/inkex/styles.py", line 33, in <module>
    from .css import ConditionalRule
  File "/tmp/.mount_Inksca347kZJ/usr/share/inkscape/extensions/inkex/css.py", line 27, in <module>
    import cssselect
ModuleNotFoundError: No module named 'cssselect'

Version info

Inkscape 1.2-beta (1b65182, 2022-04-05)