This is my first post here, sorry if this been discussed before but i serached the forum but didn't find any related topic.

I've been using Inkscape for about two years and now I updated to ver. 1.0 running on Linux mint 19.3. Now with this new update 1.0, every time I copy an object I get a pop-up window saying;

"Inkscape has received additional data from the script executed. The script did not return an error, but this may indicate the results will not be as expected."

and then it say this:

Traceback (most recent call last):
  File "ink2canvas.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 33, in <module>
    from .elements import load_svg, BaseElement, ShapeElement, Group, Layer, Grid, \
  File "/usr/share/inkscape/extensions/inkex/elements/__init__.py", line 8, in <module>
    from ._base import SVG_PARSER, load_svg, ShapeElement, BaseElement
  File "/usr/share/inkscape/extensions/inkex/elements/_base.py", line 31, in <module>
    from lxml import etree
ModuleNotFoundError: No module named 'lxml'

The copy function works but it's quite annoying to get the pop-up every time I copy something. It there anything I can do or anyway i can stop getting this message?

My guess is a clipboard manager is getting involved.  What windows manager are you using?  Does it have a clipboard manager active?  What happens when you deactivate it?

I had this problem on Manjaro Linux XFCE with CopyQ clipboard. Disabling clipboard storing was a work around solution.

Reported bug on CopyQ git:

https://github.com/hluk/CopyQ/issues/1451

EDIT:

Maybe related to this Inkscape bug:
https://gitlab.com/inkscape/extensions/-/issues/186

Possibly same bug as with Windows and Clipdiary
https://inkscape.org/en-gb/forums/beyond/error-while-copying-anything-as-long-as-clipboard-manager-clipdiary-is-active/