Pavlovia : how to save jspsych experiment to Json

URL of experiment:

Description of the problem:
The results are saved in a csv format but I would want to have them in the json format. I tried to download the jspsych.pavlovia.plugin to import a modified version in my html file but after many test I realize that I can delete all the code in it but the part and it still work perfectly for the saving. I concluded that the other functions used are not the one in my file but the one on the pavlovia server… So how can I use this modified version entirely ? and if possible, how to modify it to obtain the json files ?

Thank you