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Nick Doty @npd

What format do Mastodon blocklists take? Just a list of accounts, or of whole instances too? Could we start work on a block format that works for Mastodon, Twitter and the Web in general?

Twitter exports and imports lists that consist in Twitter UIDs (long numeric strings), as .csv files (although there's only one column); Blocktogether supports the same. A little frustrating, since it requires an API call to turn a UID into a URL or screenname.

Mastodon is also importing/exporting single-column .csv files (no metadata included, so the same format is used for blocklists and followlists), with each line as:
username@example.instance

Mastodon does support blocking entire instances, but those blocks aren't subsequently visible in the UI and aren't included in the blocklist export:
github.com/tootsuite/mastodon/