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.
-`/api/v1/accounts/:id`: The `id` parameter can also be the `nickname` of the user. This only works in this endpoint, not the deeper nested ones for following etc.
-`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.