TraitError

[rogerrouse]

In a jupyter-notebook instantiating a canvas results in a TraitError:

from ipycanvas import Canvas
can = Canvas()
TraitError: The '_canvas_manager' trait of a Canvas instance must be a _CanvasManager, but a value of class 'NoneType' (i.e. None) was specified.

Any ideas on how to fix this or what causes it?

Thanks

[martinRenou]

This has been discussed here https://github.com/martinRenou/ipycanvas/issues/295

You can either downgrade to ipycanvas==12.1 or try to upgrade your Python version