It's not currently possible to edit the title of a custom chart. It would be useful to be able to do that after a custom chart (figure) has been created.
For example, I have a dashboard with multiple charts and I forget the naming convention so would like to edit the chart titles to keep it consistent.
The workaround right now is to delete the chart and create it again. Yet right now I can't reorder the charts on a Custom dashboard so that also creates extra work to create them in the "right order".