Export

I can iterate over my selection and get all data that I need, but how can I export this data in a json file?
And, how can I export each node in selection also in a png file?
Both in a specific folder.

Firstly you need to pass this data to the plugin UI iframe, and then from that follow some tutorial on how to save files to the computer, you can find lots of info on google by searching “save file to computer js” or something like this.