A Pleroma instance can be identified by "<Mastodonversion> (compatible; Pleroma <version>)" present in `version` field in response from `/api/v1/instance`
Some apps operate under the assumption that no more than 4 attachments can be returned or uploaded. Pleroma however does not enforce any limits on attachment count neither when returning the status object nor when posting.
-`content`: a map consisting of alternate representations of the `content` property with the key being it's mimetype. Currently the only alternate representation supported is `text/plain`
-`spoiler_text`: a map consisting of alternate representations of the `spoiler_text` property with the key being it's mimetype. Currently the only alternate representation supported is `text/plain`
-`preview`: boolean, if set to `true` the post won't be actually posted, but the status entitiy would still be rendered back. This could be useful for previewing rich text/custom emoji, for example.
-`content_type`: string, contain the MIME type of the status, it is transformed into HTML by the backend. You can get the list of the supported MIME types with the nodeinfo endpoint.
-`to`: A list of nicknames (like `lain@soykaf.club` or `lain` on the local server) that will be used to determine who is going to be addressed by this post. Using this will disable the implicit addressing by mentioned names in the `status` body, only the people in the `to` list will be addressed. The normal rules for for post visibility are not affected by this and will still apply.
-`visibility`: string, besides standard MastoAPI values (`direct`, `private`, `unlisted` or `public`) it can be used to address a List by setting it to `list:LIST_ID`.
-`expires_on`: datetime (iso8601), sets when the posted activity should expire. When a posted activity expires it will be deleted from the server, and a delete request for it will be federated.
-`in_reply_to_conversation_id`: Will reply to a given conversation, addressing only the people who are part of the recipient set of that conversation. Sets the visibility to `direct`.
Pleroma has mechanism that allows frontends to save blobs of json for each user on the backend. This can be used to save frontend-specific settings for a user that the backend does not need to know about.
The parameter should have a form of `{frontend_name: {...}}`, with `frontend_name` identifying your type of client, e.g. `pleroma_fe`. It will overwrite everything under this property, but will not overwrite other frontend's settings.
This information is returned in the `verify_credentials` endpoint.