Set default colours to be fully visible #3
Description
Right now creating a new chart node gives you the options of line thickness, radius offset, line colour, and chart colour. The two colours are #000000 with alpha 0. But if a user sets up everything correctly, they will either have their chart not appear due to the colour, or they will have to manually set the alpha back to 255 every time they make a new chart.
I'd like to suggest the default colours are fully visible, with alpha 255, so it's apparent when the user is successfully adjusting their chart. This saves time for experienced users who would otherwise adjust the alpha, and makes it clear to new users that the plugin is working.