Hey :) Glad to have a reply from you too ! (and played and commented my last game jam entry ^^ will reply to it later ;))
I'm on my way to grab all the informations at once, if you let me let's say until the end of september, I could probably show you the result (I have other things to do too, and not much free time). For the moment I managed to grab the information from the fetch call and use your parser to save the data, but not in a loop for now.
At the end, perhaps it will be another script, perhaps the script could have 2 purposes : "Export all" on the main page and "Export collection" on the page collection ¯\_(ツ)_/¯ (if we can export all at once, it would be probably useless to export just a category).
What do you think ?
Cheers !
PS : the correct URL is more like this one that the one I put in my first message : https://itch.io/c/{collection_id}/{collection_slug}?page=2&format=json