Printing mark error Invalid attribute name 'inkscape:label' (1.0.x)

Summary:

Error when setting printing marks

Steps to reproduce:

• open Inkscape
• select the option to set printing marks with default options

What happened?

I got the next error:

Traceback (most recent call last):
  File "printing_marks.py", line 401, in <module>
    PrintingMarks().run()
  File "/Applications/Inkscape.app/Contents/Resources/share/inkscape/extensions/inkex/base.py", line 140, in run
    self.save_raw(self.effect())
  File "printing_marks.py", line 290, in effect
    g_center = layer.add(inkex.Group(**g_attribs))
  File "src/lxml/classlookup.pxi", line 77, in lxml.etree.ElementBase.__init__
  File "src/lxml/apihelpers.pxi", line 158, in lxml.etree._initNewElement
  File "src/lxml/apihelpers.pxi", line 317, in lxml.etree._initNodeAttributes
  File "src/lxml/apihelpers.pxi", line 333, in lxml.etree._addAttributeToNode
  File "src/lxml/apihelpers.pxi", line 1744, in lxml.etree._attributeValidOrRaise
ValueError: Invalid attribute name 'inkscape:label'

What should have happened?

Sample attachments:

Version Info:

- Inkscape Version: 1.0.1
- Operating System: macOS
- Operating System version: 10.15.7