Yes! Finally successful in getting my #dotnet7 #Blazor app to import #Mastodon Lists from a csv backup file.
It's nuts how there's actually NO W3C standard for passing array-parameters in a query: https://stackoverflow.com/a/67095427 . It's framework dependent, and is PHP dialect here.
https://docs.joinmastodon.org/methods/lists/#accounts-add wants an account_id array, but NOT in json which would be more concise.
Instead, it's fat pairs of literally { "account_ids[], "<account-id>" } for every account to add!
Reason I had to do this myself is because the existing purpose built one https://www.eliotlash.com/masto-list-importer/ instantly blows out the API rate-limits just to import 274 accounts in 27 lists.
The best it could do was recreate the missing Lists, and then dies before trying to add accounts.
So, opportunity to learn this myself with a more API efficient version, in C# / Blazor.