Earlier quoted context omitted.
They are compliant, the code being used is under the MIT license.
Yeah I'm as big of a FOSS fan as the next guy on here but you really can't complain about how someone uses your code if you used the MIT License...one of the most permissive licenses in existence. If someone wants attribution or something then they should use a license that requires that thing.
Which, as far as I can tell they haven't done. Their MIT licence claims their own copyright. No reference to the library used in readme.
https://github.com/kagisearch/privacypass-lib/blob/main/LICE...
https://github.com/kagisearch/privacypass-lib/blob/main/READ...
Usually when using apps that use MIT licensed libs they also implement a notice in a user-facing way. Google maps for instance has a (albeit hidden) section in their settings menu referencing at least one MIT licensed library.