The Expressions extension aims to model non-verbal expressions and emotional states under the ActivityStreams type model. These expressions of sound or emotion are intended to enhance or exist alongside the traditional text formats used by most ActivityPub implementations.
While ActivityStreams's existing types and extensions are very effective at supporting text communication, they can be somewhat lacking in other domains. Two of those are non-verbal and side-band communication, as preferred by many neurodivergent people. For example, some autistic individuals are uncomfortable communicating with neutral text and prefer a method that more clearly conveys emotion and tone. Plural people may additionally desire a method to identify which headmate was responsible for a particular post or interaction. These are both problems that the Expressions extension aims to solve.
In addition to making online communication more accessible, this project aims to bring a bit of lighthearted fun to ActivityPub and the Fediverse. The existing activities and extensions are very effective at communicating text and media, but they result in a very sterilized and impersonal protocol. Non-text interactions can bring a more personal touch to communication over ActivityPub.
- Misskey's "post from other account" feature
- Facebook's "feeling / activity" feature