Is there a FLOSS XMPP client for GNU/Linux that supports XEP-0224: Attention?
It's an extension for getting the attention of another user. It is also known as "nudge" or "buzz".
I'm also told mcabber can do it, although the references are sparse; it looks like there is/used to be a plugin needed, and in the current version, the UI marks contacts that want attention from you with an exclamation mark (as opposed to the regular hash sign).
You can use it via the
Note there there is currently some kind of attack possible:
/attention vulnerability with notification