1/3 columns too wide for page

I had the same issue, could you please provide an idea of how you solved this?

I went into shortcodes.css and reduced the width of .mt-one-third

Yeah I guessed after trying to use CSS overrides unsuccessfully it seems this is the only solution making it a shortcode plugin upgrade problem.

Did you ever get any reply from the plugin creator about this problem?

No i didn’t wait