apparently Mobilizon 5.2.0 broke JSON-LD stuff for the few AP implementations that care, without any announcement other than ‘bugfix: Replace joinmobilizon.org by mobilizon.org’
Smithereen seems to be the only AP implementation that actually does the LD part of JSON-LD. I find broken contexts all. the. damn. time. By far the most common mistake people make is forgetting https://w3id.org/security/v1 in actors, which makes all the public-key-related stuff not have a namespace, which makes Smithereen think there isn't a public key, which is required for an actor.
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