ModuleNotFoundError: No module named 'tinycss2'

Getting a ModuleNotFoundError: No module named 'tinycss2' error every time I try to use the extension. I'm on EndeavourOS, using the EndeavourOS repo's Inkscape package. The whole error is:

Traceback (most recent call last):
  File "/usr/share/inkscape/extensions/realscale.py", line 23, in <module>
    import inkex
  File "/usr/share/inkscape/extensions/inkex/__init__.py", line 11, in <module>
    from .extensions import *
  File "/usr/share/inkscape/extensions/inkex/extensions.py", line 34, in <module>
    from .elements import (
    ...<10 lines>...
    )
  File "/usr/share/inkscape/extensions/inkex/elements/__init__.py", line 10, in <module>
    from ._base import ShapeElement, BaseElement
  File "/usr/share/inkscape/extensions/inkex/elements/_base.py", line 40, in <module>
    from ..styles import Style, Classes, StyleValue
  File "/usr/share/inkscape/extensions/inkex/styles.py", line 31, in <module>
    import tinycss2
ModuleNotFoundError: No module named 'tinycss2'

This pops up every time I check "Live preview" or click Apply.