Hello Johannes!

Thank you for your question and feedback.

Yes, I have encountered this problem as well. In my case, I made a mistake in specifying a link between data and a visual encoding channel (like alt.X('population') instead of alt.X('pop') ). Thus, you may check the way you specify the data source.

Also, I had a problem with alt.Size and adding legend/text to each dot in a scatter plot, where I also got an empty plot. I haven't solved the problem yet.

Hope my answer can help you somehow :)

Have a great day and week ahead!

Aigerim