508 Compliance of Data Visualization

Can anybody verify the 508 compliance status of interactive data visualization with R-shiny? If it fails to meet the standards, what are the deficiencies you have found and what have you done to make your visualizations 508 accessible?

In comparison, HighCharts does a lot for 508 accessibility.

Just trying to understand what deficiencies if any that R-shiny visualization has.

Thank you for your assistance.