Why should I care?

Because it provides features that are useful no matter if you use Adobe XD with a team and use it for its "intended" purpose (a chat in the collaborative work session) or alone, writing notes to yourself.

Privacy-first

Conventionally, you'd develop a chat app (no matter for which platform) in such a way that it communicates with some external server storing the messages. Providing privacy, complying with all international laws, etc. is no small task. To have the resources to do something like that, it either has to have a high cost or sell user data to external parties (for ads, etc.).

But let's face it: We don't want that. And that's why this plugin doesn't do any of that.

Instead, the plugin stores all chat information in the document itself. It's basically like creating text layers for your conversations in the document, only with a nice, "chat-like" UI in an automated way. Also, the data gets stored in the document's metadata, meaning everything happens behind the scenes. You won't notice any of it in the document itself.

When you combine this with XD's Live Coediting feature, you basically "collaborate" on the chat data, providing a real-time chatting experience.

Finally, no personal data needs to get provided to use the plugin. Instead, nice-to-have functionalities that might decrease your privacy are purely opt-in. For example, it is pleasant for your colleagues when you provide a name (so they don't have to correspond with Anonymous), but it isn't required to use the plugin.

Open Source

Finally, the plugin is fully open-source (under the MIT license), with the source code being available at https://github.com/pklaschka/chat-xd-plugin.